- Slides: 10
Snake Venom § § § § § Chemical compound secreted by specialized poison glands. Used by the Snake to kill the prey or as a means of defense. Injected by the snake through Fangs (hypodermic needles). Clear, sticky, faint yellow or greenish colored fluid. tasteless, odorless & acidic in reaction. It is a mixture of organic compounds or enzymes (Proteolysins). Can be dissolved in water, salt solution of glycerine. It can be dried & is thermostable. It can be destroyed in Ag. No 3 , Alcohol & strong Alkakies like KOH & Na. OH.
§ Non- venomous Snakes. § Venomous Snakes. § The Snake venom is of mainly two types… § 1. Haemotoxic: destroys the blood vessels & blood cells. § Local swelling, hemorrhage , tissue damage & heart failure. § Found in Vipers. § 2. Neurotoxic: affects the CNS. , paralysis of body organs, cardiac & respiratory failure. § Found in Cobras & Kraits.
§ Approximately 20 types of enzymes found in snake venom. § Each of the enzymes has its own function. § List of the various toxins found in snake venom: 1. Proteolytic enzymes 2. Phosphomonoesterase 3. Arginine ester hydrolase 4. Thrombin-like enzyme 4. Acetylcholinesterase 5. Collagenase 6. Rnase 7. Phospholopase A 2 (A) 8. 5’- Nucleotidase 9. Phospholipase- B 10. L- Aminoacid oxidase 11. Phosoholipase- C 12. Lactose dehydrogenase 13. Adenosine triphosphatase
Sr. No Chemical Composition Mode of Action 1. Amino acid oxidants & Proteases. Affects Protein Metabolism. 2. Phosphodiesterase. Affects Cardiac System. 3. Cholinesterase. Loss of Muscle Control 4. Hyalyronidase. Increases Tissue Permeability. 5. ATP ase. Disrupt Fuel Use.
Importance of Snake venom § Ø Ø Ø Ø As Medicine: In preparation of antivenins. Copperhead venom: used against cancer in France. Enzyme from Cobra venom: treatment against Parkinson’s disease. Viper venom: can be used against osteoporosis. As a anticoagulants : helpful in treating heart disease & strokes. Rattlesnakes: blood pressure medicine. Red-necked spitting cobra : used against leukemia.
• FDA approved drugs have been developed. • Ancrod: • Malayan pit viper’s venom has ingredients which can break down blood clots. • Beneficial in treating stroke victims. • Ancrod lowers the level of fibrinogen. • Drug is given intravenously over a three to five day period after a stroke occurred. • This drug has yet to be approved by the FDA.
• Aggrastat: • Extracted from the venom of various Viper species. • Proteins responsible for anticoagulant action of the venoms. • Proteins ( disintegrins) naturally prevent platelets from sticking together. • Now synthesized in the Merck research lab. • Aggrastat (tirofiban HCL) , this drug not contain snake venom, only synthetic compound. • Designed against heart attack patients. • Got FDA approval in 1998.
Types of Venomous Snakes • • 1. Opisthoglyphs: These are rear-fanged snakes. Fangs are enlarged with a groove. Venom flows down while swallowing the prey. They are mostly harmless or mildly venomous. The Boomslang & Twig snakes are exceptions. Both were harmfull to humans.
2. Proteroglyphs: These are fixed front fang snakes. Have small non- movable front fangs. When they bite they chew to envenomate the prey. • Examples are Cobras & Kraits. • •
• Solenoglyphs: • These have movable fangs. • The fangs fold back into the mouth until they are needed. • Snakes open their mouth almost 180 degrees with fangs extended straight out. • Examples are rattlesnakes, eyelash vipers, gaboon vipers & copperheads.