Cotransmitters in the Motor Nerves of the Guinea Pig Vas Deferens: Electrophysiological Evidence

Abstract
The contractile response of the guinea pig vas deferens to motor nerve stimulation is biphasic. The first phase is antagonized by the specific adenosine triphosphate-receptor antagonist arylazido aminoproprionyl adenosine triphosphate (ANAPP 3 ), and the second by the α-receptor antagonist prazosin. The underlying electrical event, the excitatory junction potential, is also blocked by ANAPP 3 , but not by prazosin.