title: 1991 Sir Henry Wellcome Medal and Prize recipient. Medical studies of the poisonous land and sea snakes found in and around Saudi Arabia.
abstract: Studies were carried out to determine the comparative toxicity and pathophysiology of 13 of the more poisonous snakes indigenous to Saudi Arabia. Included were four snakes from the Viperidae family, six from the Elapidae family, and three representative sea snakes from the family Hydrophidae. Anesthetized adult beagle dogs and anesthetized monkeys were used in the study. Vital physiological functions were continuously recorded as were changes in the blood coagulation system and any tissue damage produced by the venom at the site of envenomation. For the intravenous administration of the venom, lyophilized venom was obtained by "milking" each of the live specimens used in the study. Actual envenomation was accomplished by grasping the poisonous reptile and allowing the snake to strike the shaved exposed gluteal muscle of the anesthetized animal. Venom from the snakes of the family Viperidae produced death in an average of 3 hours. The average lethal dose was 1.13 mg/kg. Depression of first and second stage clotting factors was observed with these venoms as well as a decrease in fibrinogen levels and in platelet counts. Findings suggestive of intravascular coagulation were also observed with moderate hemolysis of the formed elements. Some local hemorrhage was seen at the site of envenomation. Venom from the Elapidae family of snakes produced death at an average of 1.7 hours. The average lethal dose was 0.70 mg/kg. Death appeared to be primarily due to respiratory paralysis following blockade at the neuromuscular junction. Only moderate hemolysis was seen with these venoms. No intravascular coagulation or tissue damage was seen. The venom of the family Hydrophidae consistently produced death in less than 30 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Walter Reed Army Institute of Research, Washington, DC 20012.
authors.forename: J A
authors.initials: JA
authors.lastname: Vick
mesh_terms: D000328:Adult; D000818:Animals; D001363:Awards and Prizes; D004285:Dogs; D000882:Haplorhini; D006801:Humans; D012131:Respiratory Insufficiency / Q000139:chemically induced; D012529:Saudi Arabia; D012911:Snakes; D009435:Synaptic Transmission / Q000187:drug effects; D014688:Venoms / Q000633:toxicity*
chemical_list: D014688:Venoms