| age-related properties of inductive synthesis of glucose-6-phosphatase, fructose-1,6-diphosphatase, tyrosine aminotransferase and tryptophan pyrrolase in hypothalamus stimulation. | in aged rats electrostimulation of hypothalamus caused less distinct induction of the enzymes in liver tissue, kidney and spleen as compared with the adult animals. the activation of the total rna synthesis (actinomycin d and olivomycin) eliminated the alterations in the enzymatic activities, caused by the stimulation of hypothalamus. effect of adrenalectomy and administration of acth suggested that the influence of the hypothalamus stimulation on induction of the enzymes studied was realized th ... | 1975 | 3019 |
| the specificity of galactokinase induction in rat liver tissue under the effect of galactose. | in liver tissue of rats, a conventional laboratory food of which was substituted for galactose-rich food, the galactokinase activity was increased, but the glucokinase was not affected. in the rats kept on a glucose-rich food the glucokinase (but not the galactokinase) was activated. hydrocortisone injection induced an increase in tyrosine aminotransferase, but the galactokinase activity was not altered. the data obtained suggest that in rat liver tissue the galactokinase was specifically induce ... | 1975 | 3022 |
| changes in oxidative systems of liver microsomes in rats following a single administration of phenobarbital and morphine. | during the first three hours after a single administration of phenobarbital or morphine into rats a marked increase was observed in the activity and content of the respiratory chain components responsible for the oxidation of nad-h2 and nadp-h2 in liver microsomes. this activation of oxidative enzymes correlated with the disappearance of hypnotic and analgetic effects of the narcotics. the phase following the normalization of oxydative systems was characterized by the increase of microsomal enzy ... | 1975 | 3023 |
| isolation and properties of 2 kallikreins from human saliva. | two kallikreins (k-i and k-ii) were purified from mixed, parotid and submandibular human saliva. the kallikreins were separated by chromatography on cm-cellulose. the ph optima of activity were at ph 9.3 and ph 9.6-9.8; km for baee was 1.10-3m and 4.10-3m, respectively. the esterase activity of k-i and k-ii was inhibited by trasylol-like inhibitors, while the plant and synthetic inhibitors of trypsin were uneffective. in dog, rabbit and rat the hypotensive effect of k-ii and its action upon the ... | 1975 | 3025 |
| the contribution of drug research to the understanding of schizophrenia. | | 1975 | 3029 |
| the metabolism of delta4-3-oxosteroids in rat liver. | the enzymatic reactions are described by which delta4-3-oxosteroids, specially testosterone, are inactivated in rat liver. the delta4-3-oxosteroid-5 alpha-reductase in liver microsomes was studied intensively and it was found that it is an enzyme system. the 5 alpha-reduction of testosterone with nadph or with nadh depends upon different enzymes or enzyme systems. | 1975 | 3039 |
| proceedings: testosterone metabolism in liver microsomes. | | 1975 | 3042 |
| proceedings: isolated liver cells: a valuable tool for the study of drug metabolism. | | 1975 | 3043 |
| proceedings: monooxygenase activity and nicotinamide nucleotide systems in perfused rat liver. | | 1975 | 3044 |
| biochemical investigations of cancer cachexia. ii. depletion of glycogenolysis and stimulation of gluconeogenesis in walker carcinoma 256 bearing rats (author's transl). | 150-200 g heavy, walker-carcinoma bearing, male sprague-dawley-rats showed rapid, tumour weight dependent, loss of liver glycogen until complete depletion in tumour groups heavier than 40 g/animal. simultaneously the glycogen mobilization after massive glucagon stimulation, was successivly diminished and finally abolished in different groups with increasing tumor weight. concomitantly the spontaneous and stimulated activity of liver phosphorylase a was found markedly reduced in advanced tumour c ... | 1976 | 3045 |
| immunomorphological and histoenzymological analysis of adrenaline-induced myocardial necrosis (experimental study). | | 1975 | 3064 |
| factors of importance for the degree of ischemic injury in the isolated rat heart. | isolated working rat hearts were made ischemic by introducing a one-way aortic ball valve. after the ischemic period the hearts were perfused in a retrograde non-working way for 30 min. flow rates, glycogen, atp, and creatine-phosphate went down during the time of ischemia, whereas tissue lactate accumulated. for shorter periods of ischemia these values were normalized but after 30 min of ischemia the hearts seemed to be irreversibly damaged. there was a leakage of got, gpt, ldh, and cpk from al ... | 1976 | 3096 |
| effects of acidosis on myocardial contractility and metabolism. | | 1976 | 3100 |
| effects of acute metabolic acidosis on parathyroid hormone action and calcium mobilization. | mechanisms through which metabolic acidosis increases calcium mobilization have been investigated in thyroparathyroidectomized rats with induction of acute metabolic acidosis by infusing nh4c1 intravenously. acute metabolic acidosis directly raised serum calcium concentration and augmented the effect of parathyroid hormone (pth) to raise serum calcium concentration. the same effects of metabolic acidosis were observed in rats with surgically removed intestines and bilateral nephrectomy, suggesti ... | 1976 | 3111 |
| metabolism of histamine in secreting and isolated canine stomach. | total 14c activity in juice secreted by gastric pouches of six dogs and seven isolated canine stomachs was determined in response to intravenous and intra-arterial infusions of histamine and 14chistamine. the proportions of 14c attributable to histamine, nalpha-methylhistamine (nalphameh), nalpha,nalpha-dimethylhistamine (nalphanalphame2h), n-telle-methylhistamine (ntaumeh), imidazole acetic acid (imaa), n-methylimidazole acetic acid (ntaumeimaa), acetylhistamine (ach), and histaminol (hoh) were ... | 1976 | 3112 |
| intracellular bicarbonate of skeletal muscle under different metabolic states. | intracellular bicarbonate of single muscle fibers in vivo was measured by a direct electrometric method simultaneously with the membrane pd in rats under seven different metabolic states. from the measured intracellular bicarbonate values and the pco2, the bicarbonate equilibrium potential and the intracellular ph were calculated. the mean intracellular hco3- under normal control conditions was 10.3 +/- 0.7 mm (se). the intracellular bicarbonate fell significantly in both chronic metabolic acido ... | 1976 | 3113 |
| enzymes of cyclic nucleotide metabolism in invertebrate and vertebrate sperm. | | 1976 | 3138 |
| prevention of experimental gastric ulcers in rats by dial derivatives. | in 111 rats divided into 5 groups, ipronal (5-allyl-5-(beta-hydroxypropyl)-barbituric acid) protected rats from development of experimental ulceration of the gastric mucosa twice as effectively as diallylbarbituric acid and compound d2h (5-isopropyl-5-(beta-hydroxypropyl)-barbituric acid). compound d1s (alpha-allophanyl-alpha-allyl-gamma-valerolactone) was devoid of this action. | 1975 | 3148 |
| portal hypertension and gastric lesions in the rat. | gastric lesions occurred spontaneously and were increased in number by seven hours of restraint stress in rats with portal vein constriction (pvc). vagotomy and pyloroplasty protected the congested stomach from erosion formation with stress. major weight loss occurred two days after pvc, but not thereafter. platelet counts were decreased in intact and splenectomized rats with portal hypertension, but prothrombin time, partial thromboplastin time, and fibrinogen were unaffected, and histological ... | 1976 | 3151 |
| a comparative study on the irreversible binding of labeled halothane trichlorofluoromethane, chloroform, and carbon tetrachloride to hepatic protein and lipids in vitro and in vivo. | 1) after intraperitoneal injection of labeled ccl4, chcl3, and halothane in mice, 14c is preferentially bound to liver endoplasmic protein and lipid. a considerable activity is also associated with mitochondrial constituents. maximal protein binding (nmol/mg): ccl4: 2.8 (0.5 hrs); chcl3: 11.5 (6 hrs); halothane: 5 (6 hrs). lipid binding: ccl4: 6.4 (5 min); chcl3: 8 (4 hrs); halothane: 13.5 (2 hrs). the form of the binding curves in microsomal and mitochondrial protein and lipid differed with the ... | 1975 | 3152 |
| comparison of the biological effects in rat of high doses of two 4-amino-7-chloroquinoline derivatives: chloroquine and glafenine. | when given orally in elevated but nonlethal doses (150 to 450 mg/kg, on 2 consecutive days), glafenine induces in rats (body weight 100 g) a transient nephritis with an increase in blood urea, hypertrophy of adrenals, and some changes in the serum proteinogram. these effects do not appear to be due to the 4-amino-7-chloroquinoline structure from which glafenine is derived, as they are not observed with the structural analogue chloroquine given at equimolar doses under the same conditions. furthe ... | 1975 | 3153 |
| stimulation of rat liver beta-galactosidase activity by ions. | 1. the p-nitrophenyl beta-d-galactosidase asctivity in rat liver homogenates of lysosome-rich fractions was shown to be markedly affected by the ionic composition of the medium. a stimulation of the reaction rate at ph 5 was produced by most of the salts tested, which contained anions such as acetate, so4(2-) and cl-, and cations such as na+, k= and mg2+. the most pronounced effect was observed with mgcl2. only potassium glutamate was inhibitory. 2. five peaks of beta-galactosidase activity ... | 1975 | 3174 |
| regulation of pentose phosphate pathway dehydrogenases by nadp+/nadph ratios. | | 1976 | 3177 |
| cardiac adenylate cyclase. ii. structure-activity relationships for the activation of rat ventricle adenylate cyclase by beta-adrenoceptor agonists. | | 1975 | 3180 |
| actions of phenothiazine analogues on dopamine-sensitive adenylate cyclase in neuronal and glial-enriched fractions from rat brain. | | 1976 | 3181 |
| characteristics of tyrosine hydroxylation in isolated nerve endings. | | 1976 | 3182 |
| intracellular ph of cardiac muscle after administration of potassium-magnesium-aspartate (author's transl). | 27 sprague-dawley rats were anesthetized with pentobarbital. artificial ventilation was given by a starling pump respirator via a tracheal tube. intracellular ph of cardiac muscle was determined by means of the indirect procedure of measuring the distribution of 5,5-dimethyl-2,4-oxazolidinedione (dmo) in intra- and extracellular spaces (dmo-method). 12 rats were injected i.p. with 0.33 mval potassium-magnesium-aspartate/100 g body weight and 15 rats served as controls. using a regression analysi ... | 1975 | 3185 |
| pharmacological properties of 2-(2-chloro-p-toluidino)-2-imidazoline-nitrate (tolonidine), a new antihypertensive agent. iii. action on the secretions of the digestive tract and on the central nervous system, acute toxicity. | the pharmacological properties of 2-(2-chloro-p-toluidino)-2-imidazoline-nitrate (tolonidine) a new synthetic derivative of imidazoline are reported in a series of three successive articles. this compound has been shown to possess hypotensive and antihypertensive properties. after i.v. administration, the hypotensive phase was preceded by hypertension related to the potent direct alpha-sympatheticomimetic properties of the product. this pressor response, which was not seen after oral administrat ... | 1975 | 3186 |
| ionophore a23187: the effect of h+ concentration on complex formation with divalent and monovalent cations and the demonstration of k+ transport in mitochondria mediated by a23187. | the two-phase extraction technique has been used to study the equilibrium between a23187, metal cations, and h+. under these conditions the ionophore forms charge neutral isostoichiometric complexes with divalent cations in which both carboxylate groups of the 2:1 a23187:m2+ complexes are deprotonated. in ethanol, however, the methyl ester of a23187 also binds divalent cations indicating that protonated complexes between a23187 and cations should also exist. with monovalent cations, a23187 forms ... | 1976 | 3212 |
| effect of maternal diet on fetal hepatic lipogenesis. | the effects of: a, maternal diet; b, cyclic-3',5'-adenosinemonophosphate (cyclic amp) and c, clofibrate on hepatic lipogenesis in fetal rats were studied. the experimental diets contained 22% protein, 40--50% carbohydrate, adequate vitamins, and minerals. in addition, the fat-containing diets were supplemented with either 15% corn oil, 25% corn oil, or 5% cholesterol + 10% oleic acid. in the clofibrate feeding studies, 0.3% (w/v) of the ethyl ester was added to a stock ration or to fat-free diet ... | 1976 | 3221 |
| comparative solubility properties of rat and hamster zonae pellucidae. | | 1975 | 3227 |
| comparison of four proteoglycans in terms of their interactions with poly(l-arginine). | | 1976 | 3231 |
| impairment in the hepatic clearance of (35s)-bromosulphophthalein in paracetamol-intoxicated rats. | 1 the overall functional capacity of the liver was evaluated using 35s-bromosulphophthalein (bsp, 100 mg/kg, i.v.) in biliary fistulated adult rats pretreated orally with different doses of paracetamol (apap) for varying time intervals. 2 the maximal hepatic damage occurred between 12-18 h after single doses of apap (0.5 or 1 g/kg); hepatic excretory function returned to control levels by 48-72 hours. 3 administration of either 0.5 or 1 g/kg apap 18 h before bsp caused a dose-dependent inhibitio ... | 1976 | 3245 |
| dual effect of alpha-adrenoceptor antagonists in rat isolated vas deferens. | 1 in rat isolated vas deferens, the isotonic contractile responses to low doses of noradrenaline or adrenaline were antagonized, and those to high doses were potentiated, by yohimbine, piperoxan, phentolamine and tolazoline. effects due to intermediate doses were not affected, or were potentiated within about 30 min, following an initial inhibition. 2 the alpha-adrenoceptor blockers thus caused a shift to the right and an increase of the maximum height of log dose-response curves of alpha-adreno ... | 1976 | 3246 |
| the evaluation of the novel pressor activity of gamma-piperidinobutyramide (wy 20051, df480). | 1 gamma-piperidinobutyramide (wy 20051, df480) injected intravenously evoked pressor responses in the anaesthetized ganglion blocked rat preparation over the dose range 2.4 x 10(-6)-3.0 x 10(-4) mol/kg. 2 high doses (greater than 3.8 x 10(-5) mol/kg) or even repeated submaximal doses (1.9 x 10(-5) mol/kg) of wy 20051 caused tachyphylaxis of this pressor response. 3 the noradrenaline pressor-response curve was shifted significantly to the right of the control curve following a dose of wy 20051 (1 ... | 1976 | 3247 |
| electroconvulsive shock increases the behavioural responses of rats to brain 5-hydroxytryptamine accumulation and central nervous system stimulant drugs. | 1 a single electroconvulsive shock (ecs) of 150 v for 1 s increased the concentration of rat brain 5-hydroxyindoleacetic acid (5-hiaa) but did not alter brain 5-hydroxytryptamine (5-ht) or tryptophan concentrations 3 h later. 2 a single ecs decreased 5-ht synthesis 3 h and 6 h later. synthesis was back to normal after 24 hours. the ecs-treated rats did not show greater hyperactivity produced by the increased brain 5-ht accumulation following administration of l-tryptophan and tranylcypromine at ... | 1976 | 3248 |
| effects of chronic nicotine administration on the denervated rat adrenal medulla. | 1 the effects of chronic nicotine administration (1 or 10 mg/kg, s.c., twice daily) were studied in intact and denervated rat adrenal glands to determine the relative roles of central input and direct actions on catecholamines. 2 catecholamine depletion was obtained in the intact glands from 1-7 days of treatment with 10 mg/kg, with recovery by 14 days of treatment; catecholamines were not decreased in denervated adrenal glands. 3 catecholamine depletion was accompanied by a decline in functiona ... | 1976 | 3249 |
| decrease of uptake and exchange of neurotransmitter amino acids after depletion of their synaptosomal pools. | synaptosomes prelabeled at 37 degrees c with radioactive amino acids (gaba, glutamate, glycine, taurine, alpha-aminoisobutyric acid, phenylalanine, leucine) and then washed at 0 degrees c on millipore filters (dawp 02500) lost 60-70% of the accumulated radioactivity. the loss was similar with exogenous tritiated gaba and glutamate, and with 14cgaba and 14cglutamate metabolically derived from 14cglucose. in contrast, radioactive norepinephrine, dopamine and 5-hydroxytryptamine were almost totally ... | 1976 | 3261 |
| 5-ht antagonists in rat hippocampus. | | 1976 | 3262 |
| the effect of taget organ removal on the development of sympathetic neurons. | the role of target organs in the maturation of adrenergic neurons was studied in the neonatal rat. the superior cervical ganglion (scg) and its end organs, the salivary glands and iris were employed as a model system. unilateral sialectomy and iridectomy in 3-day-old animals prevented the normal development of ganglion tyrosine hydroxylase (t-oh) and dopa decarboxylase activities. these enzymes are highly localized to adrenergic neurons in the scg, and were used to monitor maturation of these ce ... | 1976 | 3264 |
| importance of o-methylation in dopamine-induced motor and behavioral phenomena. | | 1976 | 3267 |
| fractionation of nucleolar proteins by two-dimensional gel electrphoresis. | isolation of nucleolar proteins was obtained by dissociation in the presence of urea-guanidine hydrochloride, followed by high-speed centrifugation to remove nucleic acids. at least 31 fractions of nucleolar proteins were detected by isoelectrofocusing gel electrophoresis in ph range 3.5-10. following two-dimensional gel electrophoresis on sodium dodecyl sulfate-polyacrylamide slab gels, more than 100 components of nucleolar proteins were identifieid. two-thirds of nucleolar proteins were locate ... | 1976 | 3272 |
| comparison of the metabolism of benzoalphapyrene and binding to dna caused by rat liver nuclei and microsomes. | administration of 3-methylcholanthrene (3mc) to rats greatly enhanced the aryl hydrocarbon hydroxylase (ahh) activity of liver nuclei. however, the binding in vitro 3hbenzoalphapyrene (bp) to dna within the nuclei which occurred at the same time as hydroxylation of bp was much less enhanced. thin layer chromatography of the metabolites of bp produced by these nuclei revealed the same metabolites in similar relative amounts as were produced by rat liver microsomes prepared from rats which had rec ... | 1976 | 3285 |
| the repression and derepression of hepatic tyrosine aminotransferase by carcinogens. | like hydrocortisone, a single carcinogenic dose of dimethylnitrosamine (50 mg/kg) initiates the induction cycle for hepatic tyrosine aminotransferase in adrenalectomized rats. however, following this initial induction in the presence of dimethylnitrosamine, the enzyme becomes refractory to reinduction by known inducers. the administration of thioacetamide to either adrenalectomized or intact rats leads to an immediate and progressive loss of inducibility by hydrocortisone, dibutyrylcyclic amp or ... | 1976 | 3287 |
| effect of intratumoral injection of bacterial and viral neuraminidase in rats. | we studied the effect of neuraminidase injection in rat's tumor at different doses: 5,10,50,100, 500 u and we concluded that: there was no difference between the rats treated with 5,10,50 u and the controls. the y died 3 weeks after the injection. but the rats treated by 100 at 500 u of na died quickley, in the week, of long metastases. | 1975 | 3291 |
| contribution of tissue acidosis to ischemic injury in the perfused rat heart. | the isolated perfused working rat heart preparation has been used to study the effects of respiratory acidosis on myocardial metabolism and contractilly. hearts were perfused with 5 mm glucose and 10(-2) u/ml of insulin in order to enhance metabolsim of glucose relative to that of fatty acids. after perfusion with krebs bicarbonate medium at ph 6.6, hearts rapidly ceased performing external work and peak left ventricular pressure fell by 75% after 5 minutes. oxygen consumption, rate of atp gener ... | 1976 | 3293 |
| measurement of 25-hydroxyvitamin d3 in serum. | we describe a method for measuring 25-hydroxyvitamin d3 in serum. extraction with dichloromethane/methanol (2/1 by vol), followed by chromatography on a column of sephadex lh-20, resulted in an overall analytical recovery of 82% +/- 3.5% (sd). diluted normal rat serum was used as binding protein because it contains a transport protein that has both a high affinity (ka = 2 x 10(10) liter/mol) and a high capacity (3 x 10(-6) mol/liter) for 25-hydroxyvitamin d3. there is no advantage in using more ... | 1976 | 3295 |
| secretory mechanism of thyroid hormones. (ii) nadph dependency and cyclic amp. | | 1976 | 3302 |
| the haemodynamic effects of metabolic acidosis in the rat. | 1. the effect of metabolic acidosis of 4-6 h duration on cardiac output, blood pressure, heart rate, and hepatic and renal blood flow has been studied in the rat. 2. in anaesthetized rats, blood pressure and heart rate fell linearly with blood ph in both sham-operated and nephrectomized rats. there was no significant difference between the two groups in the effect of acidosis on either variable. 3. cardiac output showed a significant fall with increasing acidosis in the conscious rat. 4. estimat ... | 1976 | 3306 |
| the effect of acidosis on lactate removal by the perfused rat kidney. | 1. the isolated perfused kidneys of fed rats in normal acid-base status showed a constant rate of lactate removal from the perfusate between 5 and 90 min of perfusion at a perfusate ph of 7-4-7-5. 2. lactate removal by kidneys of rats in normal acid-base status was stimulated within 30 min by a reduction in perfusate ph to 7-1-7-2, but depressed when perfusate ph was reduced further. 3. kidneys taken from rats previously made acidotic and perfused with media of various ph values showed a progres ... | 1976 | 3307 |
| ultrasound and communication in rodents. | | 1976 | 3310 |
| the electrophysiological characteristics of glucose absorption of the goldfish intestine as compared to mammalian intestines. | | 1976 | 3331 |
| the effect of hypothermia (25 degrees c) on the circulatory system of the rat. | | 1976 | 3336 |
| effect of water deprivation on antidiuresis in dipodomys spectabilis and rattus norvegicus. | | 1976 | 3338 |
| the effect of cold exposure on liver mitochondrial and peroxisomal distribution in the rat, hamster and bat. | | 1976 | 3343 |
| aryl acylamidase activity in larvae of the webbing clothes moth, tineola bisselliella. | | 1976 | 3353 |
| the binding of catecholamines to the serum proteins of the rat and the domestic fowl. | | 1975 | 3370 |
| postnatal development of the circadian rhythm of rat liver tyrosine aminotransferase activity. | the rhythm of tyrosine aminotransferase (tat) activity in 2-day old rats is characterized by a maximum at the beginning and a further one at the end of light-time. in 7-day old animals, the rhythm is much less pronounced than in 2-day old pups. at the 21st day of life, the rats already exhibit the rhythmic pattern of the adults, although the absolute values are still somewhat below those of the adults. the tat rhythm in neonates is obviously generated by periodic variations in cyclic amp-depende ... | 1975 | 3392 |
| the influence of dehydrocholate on hepatic uptake and biliary excretion of 3h-taurocholate and 3h-ouabain. | the hepatic uptake and biliary excretion of 3h-taurocholate and 3h-ouabain was studied in the rat during saline (control) and dehydrocholate infusions. dehydrocholate (140 mumol/hr) did not influence the plasma disappearance nor the biliary excretion of taurocholate after a single iv injection (37 mumol/kg). bile production in the dehydrocholate experiment was increased 2- to 3-fold compared with controls. the biliary transport maximum for exogenously administered taurocholate was determined by ... | 1976 | 3395 |
| monooxygenase-catalyzed aldrin epoxidation and dihydroisodrin hydroxylation in monkey liver needle-biopsy specimens. assay and properties. | aldrin epoxidation and dihydroisodrin (1,8,9,10,11,11-hexachloro-2,3-7,6-endo-2,1-7,8-endo-tetracyclo 6.2.1.1(3), (6).0(2), (7)dodec-9-ene (dhi) hydroxylation have been studied in 0.2-ml liver monooxygenase preparations. liver biopsy specimens of rhesus (macaca mulatta) and bonnet (m. radiata) monkeys obtained with a 1.9-mm menghini needle were the primary enzyme sources. dieldrin and monohydroxydihydroisodrin (dhi-oh) were the only metabolites detected by electron-capture glc analysis of hexane ... | 1976 | 3398 |
| in vitro metabolism of 1-phenyl-2-propanone oxime in rat liver homogenates. | 1-phenyl-2-propanone oxime is a known in vitro metabolite of amphetamine. further in vitro metabolism of this oxime with the 12,000g supernatant fraction from homogenized rat liver gave one major and two minor metabolites which were identified as 2-nitro-1-phenylpropane, benzyl alcohol, and 1-phenyl-2-propanone, respectively, by means of combined gas chromatography and mass spectrometry, and by comparison with authentic samples of each product. | 1976 | 3399 |
| anaerobic release of fluoride from halothane. relationship to the binding of halothane metabolites to hepatic cellular constituents. | halothane has been found to undergo a reductive defluorination. this reaction requires an active cytochrome p-450 system and nadph, and is inducible by phenobarbital and polychlorinated biphenyls but not by methylcholanthrene. the fluoride release occurs only under low o2 tension, while high o2 tension results in the oxidation of halothane to trifluoroacetic acid, inorganic bromide, and chloride. the release of the inorganic fluoride is linear up to 60 min. because the conditions required for fl ... | 1976 | 3400 |
| microsomal spectral properties and narcotic n-demethylase activity in methadone-dependent rats. | rats were given access ad lib. to various concentrations (0.3 to 1.0 mg/ml) of methadone hydrochloride dissolved in sucrose solution. the n-demethylation of various narcotics was studied in hepatic preparations from methadone-consuming rats in order to determine if there was substrate specificity for the microsomal demethylase system. the vmax for the n-demethylation of methadone, ethylmorphine, and meperidine was increased by 40-65%, whereas that for morphine n-demethylation was reduced to 55% ... | 1976 | 3401 |
| physiological disposition and metabolism of n-t-butylarterenol and its di-p-toluate ester (bitolterol) in the rat. | the metabolism and disposition of the bronchodilator, n-t-butylarterenol (tba) and its di-p-toluate ester (bitolterol) were compared in the rat. radioactivity was preferentially retained in lungs of rats compared with heart and blood after iv medication with tritium-labeled bitolterol, but was not retained in tissues after iv medication with 3htba. after oral and iv medication with 3hbitolterol, fecal radioactivity accounted for 24% of the dose and 65 and 79% of the radioactivity, respectively, ... | 1976 | 3403 |
| binding of organic compounds to rat liver and lung. | the binding of various radioisotopically labeled organic compounds to rat liver and lung was investigated in vitro. pieces of rat lung and slices of rat liver were incubated at 37 degrees c under a nitrogen atmosphere in a modified krebs-ringer phosphate solution (ph 7.4) containing the compound to be studied. of the neutral compounds investigated, digitoxin, digoxin and dexamethasone were highly bound to both liver and lung tissue, whereas the degree of binding of amitrole, erythritol, and ouab ... | 1976 | 3406 |
| pharmacokinetics of digoxin in the rat. | previous studies on the pharmacokinetics of 3h-digoxin in the rat have been based on total radioactivity in the plasma, even though the drug is extensively metabolized in this species. a comparison of total radioactivity vs. unchanged drug in rat plasma after administration of 3h-digoxin clearly showed the need to separate digoxin from its metabolites. the pharmacokinetics of digoxin were therefore examined using solvent extraction and thin-layer chromatography to isolate unchanged drug. digoxin ... | 1976 | 3407 |
| the coupling of beta1-24-corticotropin to the adenylate-cylase system in rat adipocytes. evidence for hormone-nucleotides interaction (author's transl). | the general aim was to define some of the most important parameters involved in the coupling step between the synthetic analog of adrenocoricotropin hormone (beta1-24-corticotropin tetracosa peptide) and the catalytic unit of the adenylate-cyclase system of fat cells. these studies were performed with a purified plasma membrane fraction from rat adipose tissue. in this regard, some effects of ions, ph, and nucleotides (atp nad gtp) on this hormone sensitive system were studied a simple model ... | 1976 | 3415 |
| effects of chemical stimulation of the mesolimbic dopamine system upon locomotor activity. | the effects of local injections of drugs into terminal areas of the mesolimbic dopamine system were investigated. bilateral administration of dopamine, but not of noradrenaline and serotonin, into the nucleus accumbens of non-pretreated rats resulted in stimulation of locomotor activity. no clear or only minor effects were seen after injections of the dopamine metabolites 3-methoxytyramine, dopac and hva and after injections of media with different ph and osmolality. d-amphetamine proved more ef ... | 1976 | 3421 |
| syphacia muris: response to environmental stimuli when hatching in vitro. | | 1976 | 3425 |
| effect of pge1 on lipogenesis in perfused rat liver. | in perfused livers of 24 hour-fasted rats, pge1 (prostaglandin e1) infused continuously into the perfusate, was found to cause a 45% increase in the incorporation of 1-14c acetate into liver fatty acids. pge1 was found to have no effect, however, on the activity of the key lipogenic enzymes. | 1976 | 3426 |
| an amnesic effect of benzodiazepines in rats? | | 1976 | 3429 |
| the reconstruction of enzymic lipid peroxidation systems from microsomes of various origin. | | 1976 | 3437 |
| the temperature, ph, and partial pressure of oxygen in the cervix and uterus of women and uterus of rats during the cycle. | changes in the temperature, ph, and partial pressure of oxygen (po2) in the cervical canal and cavum uteri were measured in women with or without an intrauterine device and in the uteri of rats throughout the cycle. only the po2 exhibited significant variations, rising during the ovulatory phase in both cervices of women and uteri in rats. it is speculated that the rise in po2 is related to the function of these organs as reservoirs for spermatozoa. | 1976 | 3445 |
| identification of dimethylnitrosoamine metabolites in vitro. | the incubation of dimethylnitrosoamine (dmna) in the presence of rat liver microsomes leads to production of formaldehyde, formic acid, methylamine, and n-methylhydrazine. when ph 5-enzymes are added to the medium there is also the formation of n-methylhydroxylamide and n,n-dimethylhydrazine. the last compound is the only metabolite produced, to a lesser extent, by the ph 5-enzymes. thus, the denitrosated or non-denitrosated metabolites are produced either by an oxidative dealkylation and by a r ... | 1975 | 3448 |
| properties of aryl hydrocarbon hydroxylase in microsomes of morris hepatoma 5123d and the host liver. | properties of aryl hydrocarbon hydroxylase in the microsomes were compared between morris hepatoma 5123d and the host liver from rats bearing this tumor. requirement of nadph for the assay of the enzyme activity was observed, compared to that of nadh, and also the additive effect of nadh on the requirement of nadph was found in the tumor and liver. curve of ph optimum of the enzyme activity in tumor and liver differed between the rats treated with corn oil and those with 3-methylcholanthrene, in ... | 1975 | 3450 |
| pyridoxal-5-phosphate-dependent enzymes in riboflavin deficiency. | | 1975 | 3468 |
| muscarinic acetylcholine receptor from rat brain. partial purification and characterization. | a protein capable of binding atropine and (3h)propylbenzilylcholine mustard was solubilized and purified (200-fold) from rat brain. pronase and trypsin, but not phospholipases, diminished the binding capacity of the solubilized receptor. the molecular weight of the salt-solubilized receptor as determined by gel filtration in the absence of detergents is 30,000. the purified protein showed specificity of binding toward muscarinic ligands. the high and low affinity dissociation constants of the re ... | 1976 | 3500 |
| a deoxyribonucleic acid kinase from nuclei of rat liver. purification and properties. | a dna kinase has been partially purified from rat liver nuclei by a procedure which also yields dna ligase. the kinase uses atp to phosphorylate specifically the 5'-hydroxyl termini of oligodeoxynucleotides and of single- or double-stranded dna, yielding 5'-phosphate termini and adp. the kinase is inactive on rna, or on oligodeoxynucleotides of chain length less than approximately 10 to 12 residues. the kinase requires a divalent cation (mg2+, mn2+, co2+, zn2+, ni2+, or ca2+) for activity and ha ... | 1976 | 3504 |
| inorganic phosphate homeostasis. renal adaptation to the dietary intake in intact and thyroparathyroidectomized rats. | the possibility of renal tubular adaptation to variations in dietary inorganic phosphate (pi) was investigated in intact and thyroparathyroidectomized (tptx) rats pair-fed diets containing low, normal, and high amounts of pi for periods up to 10 days. clearances were measured before and during active i.v. infusions with pi in conscious animals. thus tubular reabsorption of phosphate (trpi) could be assessed over a wide range of plasma phosphate concentrations (pip1). it was found that the renal ... | 1976 | 3518 |
| identification and characterization of a bile acid receptor in isolated liver surface membranes. | it is generally assumed that hepatic transport of bile acids is a carrier-mediated process. however, the basic mechanisms by which these organic anions are translocated across the liver cell surface membrane are not well understood. since carrier-mediated transport involved binding of the transported molecule to specific receptor sites, we have investigated the possibility that bile acid receptors are present in liver surface membranes. isolated liver surface membranes were incubated at 4 degree ... | 1976 | 3520 |
| toxaphene degradation by iron(ii) protoporphyrin systems. | | 1976 | 3525 |
| characterization of fatty acid desaturase activity in rat lung microsomes. | preparations of rat lung microsomes containing 0.030-0.050 nmole of cytochromes p-450 and b5 per mg microsomal protein have been observed to contain significant levels of fatty acid desaturase activity. both stearoyl coa and palmitoyl coa are desaturated to their monounsaturated analogues, oleic acid and palmitoleic acid, respectively. activity (per mg microsomal protein) of the lung preparations varied according to the diet of the animals prior to killing in the order: fat free diet greater tha ... | 1976 | 3614 |
| effect of unilateral and bilateral castration and cryptorchidism on serum gonadotrophins in the rat. | the effects of unilateral and bilateral cryptorchidism and castration on serum concentrations of testosterone, fsh and lh in adult male rats were examined. the results provide no evidence for compensatory growth or development of the remaining scrotal testes up to 32 days after unilateral castration, although the scrotal testis of unilaterally cryptorchid rats showed enlargement when compared with those of control rats (p less than 0 - 05) at 32 days. unilateral treatments had few significant ef ... | 1976 | 3615 |
| further evidence for histamine facilitating oestrogen action in the uterus. | the effect of doses of estradiol ranging from 0-0125 to 1-6 mug on the uterine weight of the spayed rat was studied 24 h after a single s.c. injection of the hormone. the lowest dose inducing a significant increase in uterine weight was 0-32 mug. when histamine dihydrochloride (50 mg) was simultaneously injected with the hormone, the effect of small doses of oestradiol (0-0125--0-2 mug) was significantly increased. when oestradiol and histamine were administered for 3 successive days, the uterin ... | 1976 | 3616 |
| prolactin stimulation test with perphenazine: an evaluation of plasma prolactin levels and pituitary secretory activity in the rat. | many investigations of the regulation of prolactin synthesis and release are based on single plasma prolactin determinations. the purpose of the present experiment was to ascertain whether groups of rats (i.e. young or adult, male or female animals, being either intact, gonadectomized or gonadectomized and treated with oestrone), differing in age and/or endocrine status, will react to a single dose of perphenazine by an acute release of pituitary prolactin in proportion to their initial plasma ... | 1976 | 3617 |
| cytochrome redox potential dependence on substrate in rat cerebral cortex slices: importance of cytoplasmic nad(p)h and potassium. | | 1976 | 3625 |
| oxidative metabolism of the cerebral cortex of the rat in severe insulin-induced hypoglycaemia. | | 1976 | 3630 |
| glycerol kinase and dihydroxyacetone kinase in rat brain. | | 1976 | 3631 |
| neurogenic influences of bilateral adrenalectomy on monoamine oxidase. | bilateral adrenalectomy (10 days) increased the monoamine oxidase activity of the rat heart, vas deferens, spleen, superior cervical ganglion, and hypothalamus but not that of the rest of the brain, kidney, and liver. experiments were made to determine whether the increased activity was due to neurogenic influences and whether the enhanced activity of monoamine oxidase was intra- or extraneuronally located. ganglionic blockade with chlorisondamine failed to alter the rise in cardiac monoamine ox ... | 1976 | 3640 |
| oestrogenic sensitivity of rat uterine secretion. | ovariectomized adult rats with closed uteri were treated for 7 days with different oral and s..c. doses of oestradiol, oestrone, oestriol and ethinyl oestradiol. all treatments elicited the production of uterine fluid and the potencies of oestrogens were related to the amount of fluid secreted. ethinyl oestradiol and oestradiol displayed similar activity when given s.c. a daily dose of 0-003 mg oestradiol/kg resulted in about 700 mg fluid. oestrone was 3-10 times and oestriol about 100 times les ... | 1976 | 3646 |
| calcium sequestration by subcellular fractions isolated from vascular smooth muscle: effect of cyclic nucleotides and prostaglandins. | | 1976 | 3659 |
| biochemical properties of cyclic nucleotide phosphodiesterase in metastasizing and nonmetastasizing rat mammary carcinomas. | the biochemical properties of cyclic nucleotide phosphodiesterases in a nonmetastasizing and a spontaneously metastasizing rat mammary carcinoma were compared. the phosphooiesterases in both tumors had a ph optimum of around 8.0 and preferentially hydrolysed cyclic purine nucleotides. the rate of hydrolysis of purine nucleotides in the nonmetastasizing tumor was two times higher than in the metastasizing tumor, but the rate of pyrimidine nucleotide hydrolysis was equal in both tumors. theophylli ... | 1976 | 3660 |
| the role of hco3- atpase in h+ /hco3-secretion (author's transl). | active buffer transport, e.g. h+ -secretion by stomach and kidney and hco3--secretion by pancreas and salivary glands, is linked with the presence of a hco3-stimulated atp-phosphohydrolase. in contrast to (na+ -k+)-atpase which is considered to be equivalent to the na+ pump, the hco3--atpase requires only one ion for activation and is insensitive to ouabain. the hco3--atpase is found in the plasma membrane of the epithelia, but in contrast to the (na+ -k+)-atpase it is located in the luminal cel ... | 1976 | 3681 |
| inhibition of phenylalanine hydroxylase activity by alpha-methyl tyrosine, a potent inhibitor of tyrosine hydroxylase. | | 1975 | 3704 |
| the influence of diet on the lipogenic response to thyroxine in rat liver. | | 1975 | 3705 |
| effect of thyroid status and cold stress on tyrosine hydroxylase activity in adrenal gland and brown adipose tissue. | | 1976 | 3708 |
| amino acid incorporation by nuclear membrane fraction of rat liver. | | 1976 | 3709 |
| change in intracellular ph of rat liver during azo-dye carcinogenesis. | | 1976 | 3711 |
| binding of iodinated beta adrenergic antagonists to proteins derived from rat heart. | | 1976 | 3724 |
| dopaminergic neurons: activation of tyrosine hydroxylase by a calcium chelator. | | 1976 | 3726 |