Pharmacological reactions of the circular muscle of the guinea pig vas deferens.

Pharmacological responses of spiral strips prepared from the guinea pig vas deferens to various adrenergic and cholinergic agonists and autacoids were studied. On the circular muscle alpha adrenergic, muscarinic cholinergic and histaminergic receptors were identified. The responses evoked on the circular and longitudinal muscles were of the same type.