Estrogen modulates in vitro atrial bradycardia induced by Indian red scorpion venom via G-protein coupled mechanisms
Role of estrogen on cardiac dysrhythmia produced by Indian red scorpion ( Mesobuthus tamulus) venom was examined using rat right atrial preparations in vitro. In females, the M. tamulus venom produced an increase, a decrease and an increase in rate at 0.03, 0.3 and 3 μg/ml of venom, respectively, pr...
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Published in | European journal of pharmacology Vol. 546; no. 1; pp. 102 - 108 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
28.09.2006
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | Role of estrogen on cardiac dysrhythmia produced by Indian red scorpion (
Mesobuthus tamulus) venom was examined using rat right atrial preparations
in vitro. In females, the
M. tamulus venom produced an increase, a decrease and an increase in rate at 0.03, 0.3 and 3 μg/ml of venom, respectively, producing
N-shaped response curve, whereas no such response pattern was observed in males. Force of contraction in females was increased at all the concentrations of the venom, while in males the increase was seen only at 3 μg/ml. Castration of male rats did not alter the venom response to female type, while ‘estrogenisation of castrated male rats’ (pseudofemales) produced a response similar to females. Tamoxifen reversed the venom-induced responses both in females and pseudofemales. Further in females, the venom action at 0.3 μg/ml was blocked by atropine. Response at this concentration was also blocked by pertussis toxin and methylene blue. Results suggest that the cholinergic component of venom response is modulated by estrogen receptors
via G
i-protein-guanylyl cyclase mechanism. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0014-2999 1879-0712 |
DOI: | 10.1016/j.ejphar.2006.06.056 |