BINDING OF [3H]‐PRAZOSIN AND [3H]‐DIHYDROERGOCRYPTINE TO RAT CARDIAC α‐ADRENOCEPTORS
Open Access
- 1 May 1981
- journal article
- Published by Wiley in British Journal of Pharmacology
- Vol. 73 (1) , 33-39
- https://doi.org/10.1111/j.1476-5381.1981.tb16768.x
Abstract
1 [3H]-prazosin binds specifically to a single class of α-adrenoceptors in rat cardiac membranes (KD25°C = 0.2 nM). 2 That these receptors are of the α1-type was indicated by competition studies, i.e. α1-antagonists such as prazosin and (2-(2, 6-dimethoxyphenoxyethyl) aminomethyl-1, 4-benzodioxane (WB 4101) were more potent than the α2-antagonists, yohimbine and piperoxan in inhibiting [3H]-prazosin binding. 3 A comparative study of [3H]-prazosin binding and [3H]-dihydroergocryptine binding to cardiac membranes showed that both [3H]-prazosin and [3H]-dihydroergocryptine (at low concentrations) bind to α1-adrenoceptors, while [3H]-dihydroergocryptine (at higher concentrations) also binds to another class of sites.Keywords
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