RESUMO
Neuropharmacological studies have been conducted on the venom of V. russelli on experimental animals. The venom was found to produce alteration in general behaviour pattern, reduction in spontaneous motility, hypothermia, potentiation of pentobarbitone hypnosis, analgesia, reduction in exploratory behaviour pattern, muscle relaxant action, and suppression of aggressive behaviour. The venom caused a significant increase in brain GABA content in mice. The observations are suggestive of a potent CNS-depressant action of V. russelli venom.
Assuntos
Agressão/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Clorpromazina/farmacologia , Relação Dose-Resposta a Droga , Camundongos , Relaxamento Muscular/efeitos dos fármacos , Sistema Nervoso/efeitos dos fármacos , Dor/tratamento farmacológico , Ratos , Convulsões/tratamento farmacológico , Sono/efeitos dos fármacos , Venenos de Víboras/farmacologia , Ácido gama-Aminobutírico/biossínteseRESUMO
Lethal and haemorrhagic activity of Russell's Viper venom was compared against polyvalent bivalent commercial antiserum and monovalent antiserum raised in rabbit. Formaldehyde-detoxified venom offered 7-fold protection against lethal activity and 12.5-fold against haemorrhagic activity of the venom. Whole venom and formaldehyde-detoxified venom along with Freund's complete adjuvant, injected in rabbits produced high titre antiserum. Amongst all the six antiserum tested, the monovalent antiserum raised in rabbit, showed maximum precipitating bands in immunogeldiffusion and immunoelectrophoresis. The toxoid-antiserum offered maximum protection against the venom-induced lethality and the monovalent antiserum offered maximum protection against haemorrhagic activity.
Assuntos
Animais , Hemorragia/induzido quimicamente , Soros Imunes , Masculino , Camundongos , Venenos de Víboras/antagonistas & inibidoresRESUMO
Tentacle extract of the common jellyfish A. rabanchatu, caused glycaemic alteration in fasting rabbits. Intravenous administration of the extract produced a significant rise followed by a significant fall in blood sugar level. Glucose tolerance in rabbits was also significantly increased. Extract-mediated hypoglycaemic response was fully abolished in alloxan diabetic rabbits. Preliminary separation on Sephadex G 50 indicated the hypoglycaemic factor to be a non-lethal protein of molecular weight less than 20 kDa. Heat treatment of extract and G 50 separated fraction P2 demonstrated total loss of hypoglycaemic activity.
Assuntos
Animais , Glicemia/metabolismo , Venenos de Cnidários/isolamento & purificação , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/isolamento & purificação , Masculino , CoelhosRESUMO
Tentacle extract of A.rabanchatu, produced a fall of blood pressure in cat, rat and guinea pig. Hypotension produced in cat remained unantagonized by blockers of acetylcholine, histamine and 5-HT. On isolated guinea pig heart, the extract significantly reduced the rate and amplitude of contraction leading to irreversible cardiac arrest. In cats and rats, the respiratory rate and amplitude was decreased significantly and resulted in temporary apnoea. The extract also produced vasoconstriction in perfused rat hindquarter preparation and increased cutaneous capillary permeability. The extract produced contraction in several isolated smooth muscle preparations. Contraction on guinea pig ileum was partly antagonized by atropine and cyproheptadine. On isolated rat phrenic nerve diaphragm and chick biventer cervicis, the extract produced irreversible blockade of the electrical stimulation-induced twitch responses. Haemolytic and myonecrotic activity was exhibited by the extract. LD50 was found to be 7.7 mg/kg (iv, mice).