| secretin, cholecystokinin and newer gastrointestinal hormones (first of two parts). | | 1976 | 3738 |
| histamine-sensitive adenylate cyclase in mammalian brain. | | 1976 | 3741 |
| antagonistic effects of gaba and benzodiazepines on vestibular and cerebellar neurones. | | 1976 | 3742 |
| action of opiates, antipsychotics, amphetamine and apomorphine on dopamine receptors in rat striatum: in vivo changes of 3',5'-cyclic amp content and acetylcholine turnover rate. | | 1975 | 3748 |
| non-barbiturate intravenous anesthetics. | | 1976 | 3750 |
| diet, exercise and ketone metabolism. | | 1976 | 3751 |
| impaired urinary acidification in the hypothyroid rat. | since abnormalities in the renal handling of sodium and water in both the proximal and distal tubule have been described in primary hypothyroidism, this study was undertaken to examine renal tubular hydrogen secretion in this disorder. metabolic acidosis was induced in hypothyroid rats (h) and their age matched controls (c) by the administration of an oral ammonium chloride load of 0.15 g/24 h/kg for three days. on day 3 animals were prepared for clearance and acid-base studies, receiving an inf ... | 1976 | 3759 |
| editorial: mechanisms of the antihypertensive action of beta-blocking agents. | | 1975 | 3765 |
| early diagnosis of gas gangrene in laboratory animals by means of measurements of oxidation-reduction potential (eh) and acidity (ph). | | 1976 | 3774 |
| the effect of hydrocortisone and insulin on the activity and isoenzymes of typrosine-alpha-ketoglutarate transaminase in the ctyostructures of the livers of rats of different ages. | administration of hydrocortisone or insulin and also a simultaneous use of these hormones in a high dose caused a marked elevation of the total activity of tyrosine-alpha-ketoglutaric transaminase and its anode and cathode isoenzymes in the soluble fraction of the liver in the sexually immature (weighing 100-110 g) and mature (weighing 180-200 g) male rats. the stimulating effect of insulin was sharper in the young in comparison with adult animals. administration of hydrocortisone caused a more ... | 1975 | 3778 |
| chronic toxicity of 4-3'-diethylamino-2'hydroxypropyl-ajmaline hydrogen tartrate (tachmalcor) in the rat. | | 1976 | 3809 |
| performance enhancement effects of d-amphetamine, methylphenidate, pipradrol and phenindamine in rats. | a multiple behavioral schedule with food reinforcement was designed to measure the drug-induced performance enhancement and non-effective activity in rats. the schedule, 20 min in duration, had crf components in the 33 trials and extinction components in the inter-trial periods. during each trial, food reinforcement was present in the limited period (8 sec each) which was preceded by a discriminative stimulus (1 sec, either a light or a footshock). the rats generated a high rate of lever pressin ... | 1976 | 3816 |
| effect of intraventricular administration of 6-hydroxydopamine on the radiation stress induced increase in plasma corticosterone. | | 1975 | 3822 |
| psychotropic drugs and dopamine uptake inhibition. | | 1975 | 3829 |
| noradrenergic subsensitivity of rat liver homogenates during chronic ethanol ingestion. | prior studies indicated that chronic ethanol feeding induced noradrenergic subsensitivity of the cerebral cortex. sensitivity was measured using the camp response of brain slices to norepinephrine (ne). in the present report we investigated the possibility that noradrenergic receptors in a visceral organ might be similarly affected by ethanol feeding. the camp response of liver homogenates to ne was measured. chronic ethanol ingestion induced subsensitivity of the liver to ne similar to that obs ... | 1976 | 3831 |
| acid hydrolases in the odontoblast-predentin region of dentinogenically active teeth. | the presence of hyaluronoglucosidase (ec 3.2.1.35; hyaluronidase), beta-n-acetylglucosaminidase (ec 3.2.1.30), exo-1,4-beta-xylosidase (ec 3.2.1.37), and arylsulfatase (ec 3.1.6.1) in dentinogenically active odontoblasts isolated from the rat incisor has been demonstrated by means of biochemical methods. the possible function of these enzymes in relation to the calcification process is discussed. | 1976 | 3847 |
| changes of protein metabolism following irradiation. ii. protease activity, protease pattern, protein and free amino acids in the cytoplasm and cell organelles of the rat liver following 600 r whole-body irradiation. | the protease activity of cytoplasm and cell organelles of the rat liver against liver protein and hemoglobin as a substrate increases during an initial reaction phase on the first day after 600 r whole body x-irradiation. this is probably a consequence of the degradation of cellular debris. the protein, the protease activity and the free amino acids of the cytoplasm and the cell organelles decrease during the disease phase on day 3 and 4 after irradiation. the protein loss of the liver is theref ... | 1976 | 3868 |
| dynamics of the changes in the tissular levels of cyclic amp after cobalt-60 gamma-irradiation. | the total amounts of cyclic amp in liver, brain and intestinal mucosa have been measured in rats, at constant intervals, up to 18 days after whole body exposure to either a unique moderate dose (500 rd) or a unique lethal dose (750 rd) of cobalt-60 gamma-radiation. this radiation, even in a lethal dose, was found to induce no significant changes in the hepatic levels of camp. in contrast, an abrupt short-lasting increase in the levels of camp was observed in brain and intestinal mucosa after a 5 ... | 1976 | 3869 |
| peculiarities of acid-base reserves in aging. | the age-dependent peculiarities of the acid-base balance at rest and with standard loads were studied in 466 rats. it was found that with age the ph value of blood decreases, the tension of the carbonic acid increases, but the values of bb, be, sb, and ab do not undergo any significant changes. with loads, old animals showed more profound changes in the system and these changes were of decompensated character. the maximal changes in young animals were registered 1.5 hours after loading, in old r ... | 1976 | 3873 |
| cerebral manifestations in the hepatic coma syndrome (author's transl). | the pathogenesis of hepatic encephalopathy has been investigated in a two-stage devascularization model in the rat with portavacal shunt and hepatic artery ligation. there is a significant increase in brain octopamine and phenylethanolamine and a decrease in brain norepinephrine (ne) 6 to 9 hours after hepatic artery ligation. the depletion of ne seems the sequel of diminished synthesis in the presence of an unaltered turnover rate, due to a blockade of tyrosine hydroxylase either by accumulatio ... | 1975 | 3892 |
| tissue heteroallergy in pulmonary tuberculosis. | | 1975 | 3905 |
| biological stimulators of hematopoiesis as nonspecific factors increasing body's resistance (experimental study). | | 1975 | 3907 |
| proceedings: effects of peptides regulating the release of msh and tsh and of some analogues on the spontaneous exploratory reactions in rats. | | 1975 | 3938 |
| inhibition by acidosis of adenosine 3',5'-cyclic monophosphate accumulation and lipolysis in isolated rat fat cells. | lipolysis and cyclic amp accumulation were studied in isolated rat fat cells at normal (7.4) and decreased (7.0, 6.6) ph. acidosis inhibited lipolysis and cyclic amp accumulation due to na non-competetively. maximal lipolysis (3 mum na) was inhibited by 25% at ph 7.0 and by 61% at ph 6.6 cyclic amp accumulation 5 min after 3 mum na was inhibited by 57% at ph 7.0 and by 83% at ph 6.6. between 10 and 60 minutes of incubation na-stimulated lipolysis was linear at ph 7.4, whereas a progressively inc ... | 1976 | 3944 |
| cyclic amp-dependent and independent inhibition of lipolysis by adenosine and decreased ph. | na-stimulated lipolysis and camp formation in isolated rat fat cells is inhibited by acidosis. in the present report we have examined the quantitative relationship between lipolysis and camp formation at normal and reduced ph and the possible involvement of adenosine, an endogenous inhibitor of camp formation. adenosine antagonized camp accumulation and to a considerably lower degree lipolysis, effects potentiated by acidosis. theophylline, an antagonist of adenosine effects, stimulated lipolysi ... | 1976 | 3945 |
| ecologic studies of venezuelan encephalitis virus and isolations of nepuyo and patois viruses during 1968-1973 at a marsh habitat near the epicenter of the 1969 outbreak in guatemala. | ecologic studies of venezuelan encephalitis (ve) virus at a marsh habitat near the epicenter of the 1969 outbreak in guatemala revealed that the virus was enzootic there. ve virus was isolated yearly during 1968-1973 from sentinel hamsters exposed during the rainy seasons and from mosquitoes collected during july and august 1970. hamsters yielded 41 strains of ve virus and virus was detected within 2 km of the edge of the marsh, in its interior, and at its western extreme 18 km from the central ... | 1976 | 3981 |
| a simple and sensitive assay for guanylate cyclase. | | 1976 | 3989 |
| scanning electron microscopic study of chylomicrons incubated with lipoprotein lipase. | the effects of lipolysis on the structure of chylomicrons were studied with the scanning electron microscope using rat chylomicrons incubated with purified bovine milk lipoprotein lipase for 20 minutes at ph 8.1. since the amount of albumin added to the medium was limited, some of the free fatty acids and partial glycerides formed by lipolysis accumulated in the chylomicrons. lipolyzed chylomicrons fixed with oso4 at ph 7.4 appeared in scanning electron micrographs as spheres with multiply ident ... | 1976 | 3992 |
| the use of electron paramagnetic resonance in studies of free and bound divalent cation: the measurement of membrane potentials in mitochondria. | | 1975 | 4001 |
| nadph-cytochrome p450 reductase. | | 1976 | 4018 |
| evidence for two variants of poly(adenosine diphosphate ribose) glycohydrolase in rat testis. | | 1976 | 4030 |
| estrogen-dependent trypsin-like activity in the rat uterus. localization of activity in the 12,000g pellet and nucleus. | | 1976 | 4033 |
| activity of imidazole on the hydrolysis of cyclic amp and cyclic gmp by bovine heart and rat liver cyclic nucleotide phosphodiesterases. | | 1976 | 4034 |
| enzymic hydrolysis of acetylcarnitine in liver from rats, sheep and cows. | 1. the enzymic utilization of o-acetyl-l-carnitine other than via carnitine acetyltransferase (ec 2.3.1.7) was investigated in liver homogenates from rats, sheep and dry cows. 2. an enzymic utilization of o-acetyl-l-carnitine via hydrolysis of the ester bond to yield stoicheiometric quantities of acetate and l-carnitine was demonstrated; 0.55, 0.53 and 0.30mumol of acetyl-l-carnitine were utilized/min per g fresh wt. of liver homogenates from rats, sheep and dry cows respectively. 3. the acetylc ... | 1975 | 4059 |
| properties of the reaction of gdp-mannose with endogenous polyisoprenylphosphates of liver membranes. | | 1976 | 4067 |
| hepatic and extrahepatic metabolism, in vitro, of an epoxide (8-(14) c-styrene oxide) in the rabbit. | | 1976 | 4076 |
| properties of catechol-o-methyl transferase in soluble and particulate preparations from rat red blood cells. | | 1976 | 4077 |
| optimal conditions and specificity of interaction of a distinct class of nonhistone chromosomal proteins with dna. | a subclass of nonhistone chromatin proteins with high dna affinity has been isolated from rat liver. the interaction of the isolated proteins with dna in vitro was characterized utilizing a nitrocellulose filter binding technique. the temperature, time, concentration, ionic strength, and ph dependence were characterized. optimal interaction was observed at 0.19 m nacl, ph 7.5 with a protein to dna ratio of 13 (w/w). equilibrium and kinetic competition experiments indicated that these proteins in ... | 1976 | 4089 |
| the esterification of dolichol by rat liver microsomes. | the incubation of 1-3h)dolichols with cell-free preparations from various rat tissues resulted in the formation of a labeled material which possessed the characteristics of synthetic dolichol palmitate. rat liver microsomes were found to be a good source of the acyltransferase activity, and the properties of the reaction were investigated using microsomal preparations. the reaction did not require atp, coa, or mg2+ and was stimulated by the addition of phosphatidylcholine. the esterification of ... | 1976 | 4095 |
| the effect of retinol and retinoic acid on the testicular phospholipase a activity in retinol-deficient rats. | both phospholipases a1 and a2 activities (ec 3.1.1.4) at ph 7.4 were found to be significantly decreased in retinol-deficient rat testes supplemented with retinoic acid as compared to retinol-fed controls using 1-acyl-2-1-(14)c-oleoyl-sn-glycero-3-phosphocholine as substrate. however, little or no difference was observed in phospholipase a1 activity at ph 3.0 in both groups of rats. | 1976 | 4101 |
| comparative kinetic studies on the l-type pyruvate kinase from rat liver and the enzyme phosphorylated by cyclic 3', 5'-amp-stimulated protein kinase. | the kinetics of rat liver l-type pyruvate kinase (ec 2.7.1.40), phosphorylated with cyclic amp-stimulated protein kinase from the same source, and the unphosphorylated enzyme have been compared. the effects of ph and various concentrations of substrates, mg2+, k+ and modifiers were studied. in the absence of fructose 1, 6-diphosphate at ph 7.3, the phosphorylated pyruvate kinase appeared to have a lower affinity for phosphoenolpyruvate (k0.5=0.8 mm) than the unphosphorylated enzyme (k0.5=0.3 mm) ... | 1976 | 4127 |
| studies on a 3beta-hydroxysteroid sulphotransferase from rat liver. | a steroid sulphotransferase (ec 2.8.2.2) was partially purified from female rat liver. the enzyme was active towards the substrates, dehydroepiandrosterone, epiandrosterone and pregnenolone but was inactive towards oestrogens, cholesterol and ergocalciferol. a ph optimum of 5.0 was recorded but the enzyme was unstable at low ph. the enzyme was stimulated slightly by the addition of reducing agents and inhibited by p-chloromercuribenzoate and hgcl2. crude enzyme activity was markedly stimulated b ... | 1976 | 4129 |
| presence and androgen control of an alkaline phosphatase in the nucleus of rat ventral prostate. | the presence of alkaline phosphatase (ec 3.1.3.1) activity has been demonstrated in nuclei of rat ventral prostate. this enzyme activity remained after washing of isolated nuclei with 0.5% triton x-100; an acid phosphatase initially present with the nuclear fraction was removed by this treatment. the nuclear alkaline phosphatase, examined by utilizing p-nitrophenyl phosphate as substrate, had a ph optimum of 9.5-10.3, and a broad substrate specificity: p-nitrophenyl phosphate greater than phosph ... | 1976 | 4131 |
| the effect of formate on cytochrome aa3 and on electron transport in the intact respiratory chain. | 1. formate inhibits cytochrome c oxidase activity both in intact mitochondria and submitochondrial particles, and in isolated cytochrome aa3. the inhibition increases with decreasing ph, indicating that hcooh may be the inhibitory species. 2. formate induces a blue shift in the absorption spectrum of oxidized cytochrome aa3 (a3 + a33+) and in the half-reduced species (a2 + a33+). comparison with cyanide-induced spectral shifts, towards the red, indicates that formate and cyanide have opposite ef ... | 1976 | 4141 |
| rat liver plasma membrane phospholipase a. | the plasma membranes phospholipase a2 studied in situ shows very little sensitivity for ph variations ; the optimal concentration for ca++ is 5 mm ; the enzymatic kinetics are of the michaelis type. an inactive state of the phospholipase a2 exists : when rats are injected with heparin, their plasma membranes contain a very low phospholipase a2 activity. these membranes recover a high a2 activity if they are incubated in the presence of a rat platelets lysate. treatment of membranes by nacl 1 m d ... | 1975 | 4151 |
| possible occurrence for histidyl and cysteyl residues in the catalytic center of rat liver mitochondrial d (-)-beta-hydroxybutyrate dehydrogenase. | 1. rat liver mitochondrial d(-)-beta-hydroxybutyrate dehydrogenase (submitochondrial particles and partially purified preparation) is inhibited by some dicarboxylates, especially by malonate and succinate. the inhibition is reversible and competitive with beta-hydroxybutyrate while uncompetitive with acetoacetate, nad and nadh: the inhibition is maximal at ph 6 and decrease with increasing ph. 2. diethylpyrocarbonate (which reacts preferentially with histidyl residues at ph 6.6) inactivates the ... | 1975 | 4156 |
| purification and properties of cyclic amp dependent and independent protein kinases from rat pancreas. | three protein kinases ko, k1, and kii have been extracted from rat pancreas homogenate, ko is not stimulated by cyclic amp. k1 is poorly stimulated by cyclic amp (1.3 times), ku is highly stimulated (6 times). the specificity of kii with respect to various nucleotides and cyclic nucleotides has been determined. k1 and kii account for the total cyclic amp dependent protein kinase activity in the homogenate. | 1975 | 4157 |
| interactions of phosphorylethanolamine analogs with phosphorylethanolamine-citidylyltransferase. | kinetic studies of ethanolaminephosphate-cytidylyltransferase (e.c. 2.7.7.14) from rat liver have been carried out in presence of structural analogues of ethanolaminephosphate : these compounds acted as inhibitors of the enzyme: - 2-aminoethylphosphonate behaved as a substrate and a competitive inhibitor to phosphorylethanolamine: the km value of 2-aminoethylphosphonate was nearly the same as its ki value, at ph = 5,5 (30 x 10(-3) m and 24 x 10(-3) m, respectively). - 3-aminopropylphosphonate wa ... | 1975 | 4159 |
| purification and properties of aromatic l-amino acid decarboxylase (4.1.1.28) of rat brain. | l-aromatic aminoacid decarboxylase has been purified more than thousand times from homogenates of rat brain, in several steps : centrifugation, deae-cellulose, cm cellulose, hydroxylapatite, deae sephadex. its properties have been studied, most of them on an intermediate fraction of the purification, because of the instability of the purified enzyme in spite of the addition of different stabilizing agents : the enzyme decarboxylates 5-hydroxytryptophan (5 htp) and dopa in a ratio constant throug ... | 1975 | 4160 |
| adjuvant and immunostimulating activities of water-soluble substances extracted from mycobacterium tuberculosis (var. hominis). | water-soluble substances have been extracted from two strains of mycobacterium tuberculosis var. hominis: the native hydrosoluble part (polysaccharide and peptidoglycan), a substance in which the polysaccharide moiety is less abundant than in the latter, the acetylated peptidoglycan and, finally a tetrasaccharide-heptapeptide. all four types of substances, when they were injected together with freund's incomplete adjuvant, exerted an adjuvant effect on the production of delayed-type hypersensiti ... | 1975 | 4166 |
| intrahepatic lymphoid tissue graft: course of the gvh reaction induced by peyer's patches. | to investigate the thymus-dependent immune competence of peyer's patches, the course of splenomegaly and hepatic perivascular infiltration (pvi) was studied as criteria of graft-versus-host reaction (gvhr). parental or f1 hybrid lymphoid tissues, were intrahepatically implanted and the ability of peyer's patches to induce a gvhr was compared to that of spleen, lymph nodes and thymus. a slight but significant delayed increase of spleen index was observed at the 40th post operative day following p ... | 1975 | 4168 |
| on the mechanism of action of clozapine on the adrenergic neurone. | 1 the antipsychotic drug, clozapine, lowered noradrenaline and metaraminol (ma) concentrations in the rat heart. this action was blocked by the presence of a ganglionic blocking drug. 2 other alpha-adrenoceptor blocking drugs (phenoxybenzamine, phentolamine) did not significantly lower heart amine concentrations. an inhibitor of neuronal amine uptake (desipramine) caused only a slight lowering. the combination of phentolamine and desipramine showed considerable activity, and this action was bloc ... | 1976 | 4179 |
| proceedings: the uptake of weak acids and bases into isolated rat superior cervical ganglia in relation to intracellular ph. | | 1976 | 4181 |
| proceedings: two types of intrinsic sympathomimetic activity with beta-adrenoceptor blocking drugs. | | 1976 | 4182 |
| proceedings: a rapid in vivo test for dependence potential of analgesic drugs. | | 1976 | 4185 |
| effect of sas (a new 10-n-acylaminophenothiazine) on gastric secretion and ulceration in rats. | the antiulcer and antisecretory activity of 2-chloro-10-4'(n-beta-hydroxyethyl) piperazinyl-1' acetylphenothiazine (sas) has been investigated. at 10 and 20 mg/kg (s.c.) the drug was found to possess potent antigastric secretory and antiulcer activity (both in shay and stress ulcers) and did not exhibit any peripheral parasympathetic blocking activity. the pronounced antispasmodic activity of sas was nonspecific rather than a specific parasympatholytic effect. | 1976 | 4186 |
| tyrosine hydroxylase and dopamine-beta-hydroxylase: distribution in discrete areas of the rat limbic system. | tyrosine hydroxylase and dopamine-beta-hydroxylase have been measured in 34 discrete areas and nuclei of the limbic system of the rat. both enzymes showed an uneven distribution in this system. the ratio between tyrosine hydroxylase and dopamine-beta-hydroxylase activities showed a significant correlation when compared with the ratio of dopamine and norepinephrine concentrations for the areas studied. the results strongly suggest that dopaminergic terminals are present in discrete areas of the l ... | 1976 | 4197 |
| testosterone metabolism in male rat epiphysis. | using radioactive substrate, thin-layer chromatography and recrystallization methods as well as differential centrifugation, gel filtration and electrophoresis, testosterone metabolism was investigated in male rat epiphyseal growth plate. 5alpha-androstane 3alpha-17beta-diol was found to be a major metabolite in vitro; lesser amounts of androstenedione and androstanedione, and a very small amount of 5alpha-dihydrotestosterone were also identified. radioactivity was recovered in epiphyseal subcel ... | 1976 | 4200 |
| studies on the formation by rat brain preparations of cdp-diglyceride from ctp and phosphatidic acids of varying fatty acid compositions. | the enzyme, ctp:phosphatidate cytidylyltransferase (ec2.7.7.41) which catalyses formation of cdp-diglyceride from ctp and phosphatidic acid has been studied in rat brain preparations and other tissues. improvement, as judged by the higher tissue activities obtained, in the assay method for this enzyme was achieved through use of phosphatidic acids sonicated in buffer-detergent solution saturated with ether and containing bovine serum albumin and use of short incubation times which essentially pr ... | 1976 | 4204 |
| age dependence of the number of the stem cells in haemopoietic tissues of rats. | the number and concentration of haemopoietic stem cells in the femoral bone marrow and spleen of wistar rats of different ages were investigated. stem cells were assayed by the spleen colony technique in irradiated rat recipients. the ability of the recipient spleen to harvest transplanted tissue as a macroscopic colony was found to be dependent on the recipient's age. changes with senescence were observed also in the concentration and the size of the stem cell compartment both in the marrow and ... | 1976 | 4224 |
| decreased graft versus host reaction after intrahepatic lymphoid tissue implantation. | | 1976 | 4227 |
| regulation of fatty acid synthesis. | | 1976 | 4230 |
| radioiodination of human low density lipoprotein: a comparison of four methods. | a comparison has been made of four labelling techniques used to radioiodinate human low density lipoprotein (ldl). (1) chloramine t iodination at ph 7.4 was 20-25% efficient and gave a product immunologically indistinguishable from native ldl. approximately 30% of the incorporated radioactivity, however, was found in ldl lipids, and the metabolic decay of the labelled complex in rats did not obey first order kinetics. radiolabelling at ph 10 reduced the uptake of 125i into lipids to 10% but also ... | 1976 | 4242 |
| a simple method for the cryopreservation of lymphocytes. retention of specific immune effector functions by frozen-stored cells. | a simple, quick and inexpensive method for cryostorage of lymphocytes is discribed. when injected into appropriate normal recipients, frozen-stored rat and sheep lymphocytes caused gvh and nlt reactions respectively. sheep lymphocytes remained viable after several months storage and functioned satisfactorily as 51cr-labelled target cells in assays for cytotoxic antibodies. lymphocytes, including immunoblasts, drained from sheep efferent lymphatics during immune responses to injected murine p815 ... | 1976 | 4251 |
| the development of thermoregulation in two species of woodrats, neotoma lepida and neotoma albigula. | | 1976 | 4272 |
| our experience with the method of d'amour and smith. | the authors carried out studies on a group of analgetic preparations (morphine, lydol, thylidine, pentazocine and analgine) by the method of d amour and smith, using thermic painful stimulation. the experiments were carried out on white rats-young and adult of both sexes of the strain wistar. the mean lethal dosis were determined as well as the mean effective doses and therapeutic indices. the experimental results showed that thylidine was the strongest analgetic agent with atherapeutic index of ... | 1975 | 4289 |
| blood sugar and hypoxic dynamics in metabolic acidosis and alkalosis (experimental data). | the dynamics of the glucose concentration and arterovenous glucose gradient was examined during different metabolic deviations in the acid-base balance. the metabolitic acidosis increased the level of sugar in the blood. a definite influence on the latter had the gravity of the acidosis and to a certain degree its pathogenetic form. the arterio-venous glucose difference changed from negative to positive with the increase of proton activity. the type of the peripheral hypoxic structure, formed d ... | 1975 | 4290 |
| nuclear 3alpha-hydroxysteroid dehydrogenase (3alphaohd) activity for 5alpha-dihydrotestosterone in the rat prostate. | the in vitro examination of adult male rat prostatic 3alpha-hydroxysteroid dehydrogenase (3alphaohd) activity using 5alpha-dihydrotestosterone4 as substrate indicates that significant levels of enzyme activity are associated with purified nuclei as well as with the cytosol fractions. both the purified nuclear and the cytosol fractions exhibited higher levels of 3alphaohd activity with nadh than with nadph. the ph activity curves for the nadh and nadph catalyzed reactions were different for both ... | 1975 | 4294 |
| the effects of neurally active amino acids on prolactin secretion. | several neurally active amino acids were injected into the third ventricle of anesthetized male rats. two or eight mumole of gaba produced significant increases in the plasma concentrations of prolactin (prl), indicating increased prl release from the pituitary. two mumole of glycine was also effective in elevating prl levels. the intraventricular injection of the lowest dose of gaba (1.0 mumole), glutamate (0.4 or 2.3 mumole), lysine (0.2 or 2.0 mumole), or 0.9% nacl did not alter prl levels si ... | 1976 | 4297 |
| rat-liver superoxide dismutase. purification and age-related modifications. | cytoplasmic superoxide dismutase has been purified from livers of young (6 months) and old (27 months) rats. the enzyme purified from old animals shows an age-related reduction in the specific activity, accumulation of antigenically cross-reacting material and increased sensitivity to temperature. no differences were found in the molecular weight, electrophoretic mobility, antigenicity and ki between enzymes purified from young and old rats. this is the first demonstration of age-related alterat ... | 1976 | 4328 |
| a comparison between a melanocyte-stimulating hormone inhibitory factor (mif-i) and substances known to activate central dopamine receptors. | the tripeptide, prolyl-leucyl glycine amide, a melanocyte-stimulating hormone inhibitory factor (mif-i), which has been reported to be effective in improving symptoms of parkinson's disease, has been compared with drugs known to activate dopamine receptors in rat and mouse brain. unlike apomorphine, amphetamine and amantadine it was incapable of producing sterotyped behaviour in the rat and unlike 1-dopa it was also ineffective in rats pretreated with the monoamineoxidase inhibitor mebanazine. n ... | 1976 | 4332 |
| distribution of lysosomal enzymes in different types of rat liver cells. | | 1976 | 4333 |
| activation of guanylate cyclase by sodium azide in rat adipocytes. | | 1976 | 4340 |
| influence of diurnal cycles on biochemical parameters of drug sensitivity: the pineal gland as a model. | diurnal cycles in physical parameters in the environment modulate biochemical and physiological circadian rhythms in experimental animals, including cycles in the sensitivity to external influences. environmental lighting synchronizes cycles of indole metabolism and melatonin synthesis in the rat pineal gland by modulating the activity of postganglionic sympathetic nerves. as a consequence, the sensitivity of pineal n-acetyltransferase to stimulation by isoproterenol or by dibutyryl cyclic amp v ... | 1976 | 4341 |
| hypothalamic inactivation of thyrotrophin-releasing hormone. | following the demonstration of peptidases in the rat hypothalamus which inactivate thyrotrophin-releasing hormone (trh), a sensitive and specific radioimmunoassay for the releasing hormone was used to investigate the presence of similar peptidases in the rabbit hypothalamus. trh was found to be rapidly inactivated by supernatant and particulate hypothalamic fractions, with higher peptidase activity in the supernatant than in the particulate fraction. an optimum ph of 7.3 within physiological lim ... | 1976 | 4345 |
| protective drug actions in experimental myocardial infarct. | | 1976 | 4364 |
| current viewpoints on the relaxation of the uterus. an international symposium on the use of betamimetics. | | 1975 | 4367 |
| purification and properties of klebsiella pneumoniae heat-stable enterotoxin. | the enterotoxic material in cell-free growth preparations of klebsiella pneumoniae serotype 5 was purified by sequential ultrafiltration and gel filtration (gf) procedures and the fractions were assayed for enterotoxic activity by determining their ability to induce in vivo net water secretion in the rat jejunum. whole-cell lysates were inactive. anaerobic broth culture conditions yielded a 10-fold increase in toxin production over aerobic conditions. enterotoxic activity was absent in the um-10 ... | 1976 | 4375 |
| fibrinolytic activity of the rat ovum, appearance during tubal passage and disappearance at implantation. | fertilized rat ova were histochemically examined for their fibrinolytic activity. activity was found during tubal passage, which disappeared at implantation. simultaneously the fibrinolytic activity of the endometrium disappeared at deciduation. these changes might be a prerequisite for implantation of the zygote. | 1975 | 4381 |
| effect of copper and plastic intra-uterine devices on the fibrinolytic activity of the endometrium in the rat. | the effect of copper and plastic intrauterine devices (iud) on the fibrinolytic activity of the endometrium was studied in the rat. a copper or a plastic device was placed in one of the uterine horns, while the other horn served as a control. biopsy specimens were obtained from both horns and examined histochemically. the copper concentration was determined by atomic absorption spectroscopy. the fibrinolytic activity of the control horn was found to be localized to small vessels in the outer lay ... | 1975 | 4394 |
| motility of the rat oviductal tract isolated in different stages of the sex cycle. effects of catecholamines. | physiological and pharmacological characteristics of the spontaneous motility of rat oviductal tracts (the coiled oviduct plus its mesosalpinx), isolated in proestrus, estrus or metestrus, are described. the initial contractile tension (recorded following isolation) was comparable in the three stages of the cycle, but its decrement with time was greater in metestrus than in proestrus; the opposite being observed regarding the rate of contractions. norepinephrine and phenylephrine depress motilit ... | 1975 | 4398 |
| the interrelationships between the in situ fluxes of water, electrolytes and glucose by hymenolepis diminuta. | | 1976 | 4401 |
| proline in fascioliasis: iii. activities of pyrroline-5-carboxylic acid reductase and pyrroline-5-carboxylic acid dehydrogenase in fasciola. | | 1976 | 4402 |
| studies on urinary arylsulphatase activity in vitamin a deficient rats. | urinary arylsulphatases (e.c.3.1.6.1) a and b were increased in male rats fasted for 24 hours. excretion of non dialysable protein nitrogen decreased whereas creatinine excretion increased. on refeeding diet arylsulphatase a activity was restored to normal whereas arylsulphatase b was not normalised. a single oral supplementation of vitamin a acetate (20 000 iu) to rats fasted for 24 hours resulted in a significant reduction of both arylsulphatase a and b eventhough no further reduction of prote ... | 1976 | 4403 |
| effect of long-term starvation on the rat liver lysosomes. | the effect of 120- and 240-h starvation on rats hepatocytes ultrastructure and particularly the changes of the lysosomes were studied. eelectronmicroscopically and cytochemically there have been observed diminution of the number of mitochondria and degranulation and vacuolzation of the er. at the same time golgi complex was hypertrophied and the number of lysosomes was much increased, mainly those of the autophagic type. biochemically was shown, that the activity of some acid hydrolases (beta-gl ... | 1976 | 4404 |
| properties of rat lens phosphofructokinase. | two interconvertible forms of phosphofructokinase (pfk) have been eluted from a deae-cellulose column from the supernatant fraction of rat lens homogenates centrifuged at 96,000 x g for 1 hour at 0 to 4 degrees c. the interconversion can be manipulated by a change in the ph of the extracting and eluting buffers. pfk-i is the dominant form at ph between 7.4 to 7.05, while pfk-ii dominates at ph 7.4 to 8.2. pfk-ii is believed to be the functional form; it is inhibited by high concentrations of atp ... | 1976 | 4411 |
| effects of pregnancy on the development of acute uremic syndrome in the rat. | we evaluated the contributory role which gestational metabolic adaptions may play in the development of acute uremic syndrome in rats by studying the effects of nephrectomy in pregnant and nonpregnant animals. whereas no significant differences in creatinine and uric acid concentrations were found between control and pregnant rats, urea concentrations were significantly lower in the pregnant animals before, as well as well as 6, 12 and 24 h after, bilateral nephrectomy. it is suggested that crea ... | 1976 | 4412 |
| intracellular distinction between peroxidase and catalase in exocrine cells of rat lacrimal gland: a biochemical and cytochemical study. | the lacrimal gland (glandula orbitalis externa) of rat contains both peroxidase and catalase and was used as a model for biochemical and cytochemical distinction between peroxidase and catalase. both enzymes were isolated by ammonium sulfate precipitation from tissue homogenates, and the effects of fixation with glutaraldehyde and various conditions of incubation were investigated colorimetrically using dab as hydrogen donor. the lacrimal gland peroxidase is strongly inhibited by glutaraldehyde ... | 1976 | 4418 |
| guanylate cyclase and cyclic guanosine 3':5'-monophosphate phosphodiesterase activities and cyclic guanosine 3':5'-monophosphate levels in normal and transformed fibroblasts in culture. | to investigate the role of guanosine 3':5'-monophosphate (cyclic gmp) in cultured cells we have measured guanylate cyclase and cyclic gmp phosphodiesterase activities and cyclic gmp levels in normal and transformed fibroblastic cells. guanylate cyclase activity is found almost exclusively in the particulate fraction of normal rat kidney (nrk) and balb 3t3 cells. enzyme activity is stimulated 3- to 10-fold by treatment with the detergent lubrol px. however, enhancement of guanylate cyclase by fib ... | 1976 | 4444 |
| isolation of human eosinophil phospholipase d. | phospholipase d preferentially contained in human eosinophil polymorphonuclear leukocytes as compared to other leukocytes was isolated by sequential asion and cation exchange chromatography and gel filtration. the purified eosinophil enzyme specifically liberated choline from i-alpha-phosphatidyl choline with a ph optimum of 4.5-6.0 and exhibited a pi of 5.8-6.2 on polyacrylamide-gel isoelectric focusing, which are properties shared by phospholipase d from plant sources; however, its apparent mo ... | 1976 | 4468 |
| effects of egg factors on cyclic nucleotide metabolism in sea urchin sperm. | cyclic amp in strongylocentrotus purpuratus sperm was elevated approximately 2-fold by theophylline or 1-methyl-3-isobutylxanthine. factors released from sea urchin eggs (fre) elevated sperm cyclic amp by about 7-fold within 1 min, and the combination of fre with theophylline increased sperm cyclic amp up to 100-fold within 1 min. cyclic gmp in sea urchin sperm was slightly elevated by theophylline, but was lowered by fre. cyclic gmp in sperm treated with fre plus theophylline was not higher tha ... | 1976 | 4475 |
| influence of viable yogurt microflora on digestion of lactose by the rat. | laboratory rats were fed experimental diets including yogurt, pasteurized yogurt, and simulated yogurt with sucrose or lactose for 7 days followed by a single experimental meal of yogurt, pasteurized yogurt, or simulated yogurt. assays of blood galactose demonstrated that animals fed natural yogurt containing the viable culture microflora were able to absorb galactose more efficiently. intestinal lactase activity of yogurt-fed animals was greater than in animals fed other experimental diets incl ... | 1976 | 4480 |
| evidence for the role of brain biogenic amines in depressed motor activity seen in chemically thyroidectomized rats. | | 1976 | 4580 |
| synthesis and release of prostaglandins by rat brain synaptosomal fractions. | | 1976 | 4582 |
| comparison of the effects of depolarizing agents and neurotransmitters on regional cns cyclic gmp levels in various animals. | | 1976 | 4583 |
| subcellular distribution of ketone body metabolizing enzymes in the rat brain. | | 1976 | 4586 |
| cyanide intoxication in the rat: physiological and neuropathological aspects. | sodium cyanide was given to rats by intravenous infusion at a rate that would avert apnoea (the first sign of overdosage) in the majority. there was full physiological monitoring in a group under anaesthesia and more limited monitoring in an unanaesthetized group. white matter was damaged in six animals and grey matter additionally in only one. it was concluded that cyanide can damage neurones only through the medium of secondary effects on circulation and respiration. | 1976 | 4588 |
| stability of some pyridoxal phosphate-dependent enzymes in vitamin b-6 deficient rats. | the effects of lowering the liver pyridoxal phosphate (plp) concentration by vitamin b-6 deficiency on the stability of several rat liver enzymes were examined. three plp-dependent enzymes (serine dehydratase, ornithine-delta-aminotransferase, and tyrosine aminotransferase) and two non-plp-dependent enzymes (glucose-6-phosphate dehydrogenase and phosphoenolpyruvate carboxykinase) were induced in vitamin b-6 deficient and control rats by feeding them high-protein diets or by injecting them with g ... | 1976 | 4599 |
| mass fragmentography of morphine: relationship between brain levels and analgesic activity. | morphine levels in rat brain were measured by the multiple ion detection method (mass fragmentography), using a computer-controlled gas chromatograph-mass spectrometer, and were correlated with the analgesic activity of the narcotic at intervals up to 6 hours after the injection. morphine levels in brain reached a peak of 346 ng/g of tissue wet weight 30 minutes after the subcutaneous injection of 10 mg/kg of morphine sulfate and then declined rapidly over the next 3 hours. between 3 and 6 hours ... | 1976 | 4605 |
| vasoconstrictor actions of delta8- and delta9-tetrahydrocannabinol in the rat. | cardiovascular effects of delta8- and delta9-tetrahydrocannabinol (thc) were studied after systemic intravenous administration and intra-arterial administration into a perfused vascular bed in the urethane-anesthetized rat. intravenous administration of delta8- and delta9-thc produced dose-related transient increases in blood pressure followed by more prolonged hypotensive responses and bradycardia. intra-arterial administration of delta8- and delta9-thc into the perfused hindquarters of the rat ... | 1976 | 4606 |