| characterization of the major metalloprotease isolated from the venom of the northern pacific rattlesnake, crotalus viridis oreganus. | rattlesnake venoms typically contain several different metalloproteases, some of which are hemorrhagic toxins. metalloproteases contribute significantly to the often severe necrotic changes in tissues following envenomation, and these prominent components are important to the predigestive role of venoms. venom of the northern pacific rattlesnake (crotalus viridis oreganus) contains at least five distinct metalloproteases, and the dominant protease (trivial name, cvo protease v) has been isolated ... | 1996 | 9027983 |
| resistance of california ground squirrels (spermophilus beecheyi) to the venom of the northern pacific rattlesnake (crotalus viridis oreganus): a study of adaptive variation. | recent studies have documented natural resistance to snake venom in a number of diverse mammalian species. the present paper documents for the first time variation in such resistance within one single species, the california ground squirrel (spermophilus beecheyi). this species is a frequent prey of the northern pacific rattlesnake (crotalus viridis oreganus) in certain habitats. venom resistance was tested directly in two populations of ground squirrels by injection of 1-40 mg/kg venom doses. o ... | 2012 | 3672545 |
| comparison of the protective effect of a commercially available western diamondback rattlesnake toxoid vaccine for dogs against envenomation of mice with western diamondback rattlesnake (crotalus atrox), northern pacific rattlesnake (crotalus oreganus oreganus), and southern pacific rattlesnake (crotalus oreganus helleri) venom. | to evaluate effectiveness of a commercially available toxoid manufactured from western diamondback (wd) rattlesnake (crotalus atrox) venom against envenomation of mice with wd, northern pacific (np) rattlesnake (crotalus oreganus oreganus), and southern pacific (sp) rattlesnake (crotalus oreganus helleri) venom. | 2015 | 25710764 |
| isolation and identification of a snake venom metalloproteinase inhibitor from california ground squirrel (spermophilus beecheyi) blood sera. | california ground squirrels (spermophilus beecheyi) show blood-based defenses to a variety of toxins in the venom of the northern pacific rattlesnake (crotalus oreganus oreganus). in this study we demonstrate the presence of an effective snake venom metalloproteinase inhibitor (svmpi) in s. beecheyi. the blood sera of california ground squirrels were effective at reducing the metalloproteinase activity of northern pacific (c. o. oreganus) and prairie rattlesnake (crotalus viridis viridis) venoms ... | 2011 | 21903126 |
| california ground squirrel (spermophilus beecheyi) defenses against rattlesnake venom digestive and hemostatic toxins. | previous studies have shown that some mammals are able to neutralize venom from snake predators. california ground squirrels (spermophilus beecheyi) show variation among populations in their ability to bind venom and minimize damage from northern pacific rattlesnakes (crotalus oreganus), but the venom toxins targeted by resistance have not been investigated. four california ground squirrel populations, selected for differences in local density or type of rattlesnake predators, were assayed for t ... | 2005 | 16273425 |
| california ground squirrel (spermophilus beecheyi) blood sera inhibits crotalid venom proteolytic activity. | some california ground squirrels (spermophilus beecheyi) show limited necrosis following envenomation by northern pacific rattlesnakes (crotalus viridis oreganus). this study demonstrates that s. beecheyi blood sera inhibits venom proteases. sera from rattlesnake-abundant habitats inhibited c. v. oreganus venom more effectively than venom from two allopatric rattlesnake species, c. v. viridis and c. atrox, suggesting evolutionary specialization. the pattern of inhibition among squirrel populatio ... | 2000 | 10673162 |
| assessment of rattlesnake dangerousness by california ground squirrels: exploitation of cues from rattling sounds. | we propose that the predator-prey relationship between california ground squirrels, spermophilus beecheyi beecheyi, and northern pacific rattlesnakes, crotalus viridis oreganus, offers a compelling analogy with the well-studied case of intraspecific fighting and assessment. because ground squirrels frequently place themselves at risk by harassing rattlesnakes, they stand to benefit from assessment strategies which serve to mediate risk. for example, larger and warmer snakes are more dangerous th ... | 1999 | 10373264 |
| conflict and assessment in a predator-prey system: ground squirrels versus rattlesnakes. | adult california ground squirrels, spermophilus beecheyi beecheyi, actively confront and harass northern pacific rattlesnakes, crotalus viridis oreganus, which are the principal predator of ground squirrel pups. in this report we examine the roles of risk (snake size) and context (location of encounter and squirrel reproductive category) in rattlesnake assessment by ground squirrels. in interpreting the results, we borrow heavily from the well-developed conceptual framework applied in the analog ... | 1999 | 10328789 |
| evaluating the thermal effects of translocation in a large-bodied pitviper. | acute stressors can be costly, often requiring alteration of normal physiological processes to mitigate their effects. animal translocation may be a very stressful event and result in a reduced ability to maintain homeostasis. the impacts of translocation on the thermal ecology of ectothermic vertebrates, which may rely on preferred habitats for thermoregulation, are currently unknown. in this study, 22 adult male northern pacific rattlesnakes (crotalus oreganus oreganus) were implanted with aut ... | 2014 | 24962181 |
| syncope, massive aspiration, and sudden death following rattlesnake bite. | fatalities following rattlesnake bite are rare in the united states, usually occur some hours following the bite, and are generally secondary to direct venom effects. we report a patient with acute syncope and subsequent massive aspiration resulting in airway obstruction and rapid death following a probable northern pacific rattlesnake (crotalus oreganus oreganus) bite. | 2007 | 17896845 |
| presence of peptide inhibitors in rattlesnake venoms and their effects on endogenous metalloproteases. | long-term storage of proteins with retention of biological activity is a concern for many actual and potential protein drugs. a model for stabilization of proteins for long periods could exist in natural systems, particularly among viperid snakes whose venoms are rich in lytic enzymes, because when secreted into the lumen, they are stored in an inactive and competent state for many months. one mechanism inhibiting autolysis is the production of (relatively) low affinity peptide enzyme inhibitors ... | 2005 | 15683863 |
| the role of the vomeronasal organ in rattlesnake (crotalus viridis oreganus) predatory behavior. | during predatory behavior, rattlesnakes depend primarily upon thermal and visual cues to initially aim a strike. however, it has been hypothesized that prey-related odors sensed by the vomeronasal system act as releasing stimuli of the strike and that such vomodors are primary stimuli during poststrike trailing and swallowing of the envenomated rodent. to test this, northern pacific rattlesnakes were rendered avomic by bilateral lesions of the vomeronasal nerves, and their vomic and avomic preda ... | 1996 | 8872321 |
| fibrinogenolytic proteases from the venoms of juvenile and adult northern pacific rattlesnakes (crotalus viridis oreganus). | 1. venoms of crotalus viridis oreganus show marked ontogenetic variation in protease activity. adult venoms are approximately five-fold higher in protease (caseinolytic) activity. 2. of seven potential protease inhibitors, only edta and 1,10-phenanthroline caused a significant decrease in protease activity. responses of juvenile and adult venoms were essentially equivalent, and attempts at recovery of protease activity of edta-treated venoms by the addition of ca2+ or zn2+ were unsuccessful. 3. ... | 1993 | 8403847 |
| biochemical bases for difference in oxygen affinity of maternal and fetal red blood cells of rattlesnakes. | pregnancy in crotalus viridis oreganus is associated with an increase in the nucleoside triphosphate (ntp) concentration and a concomitant decrease in the oxygen affinity of the adult red blood cell. however, although the red blood cells of non-pregnant adults and fetuses have indistinguishable ntp concentrations, they have different oxygen affinities. therefore, red blood cell ntp concentrations alone cannot account for the oxygen-affinity difference between fetal and maternal red blood cells. ... | 1993 | 8457000 |
| influence of pregnancy on the oxygen affinity of red cells from the northern pacific rattlesnake crotalus viridis oreganus. | | 1991 | 1940772 |