Pharmacological studies on the role of cholinergic nerves in the neuromuscular transmission in the circular smooth muscle of XXXX vas deferens.

@entity2997 @entity9856 @entity840 @entity4524 @entity1617 @entity2607 @entity3897 @entity3159
Effects of various drugs were examined on the mechanical responses of the circular smooth muscle of @entity840 vas deferens evoked by field stimulation and @entity1617 . During field stimulation (0.1 msec, 3-80 Hz) a contraction consisting of two (initial and second) phases occurred. In addition, another contraction (after-response) occurred after the cessation of the stimulation particularly at higher frequencies (40-80 Hz). @entity2997 (2-20 microM) suppressed both the initial and second phases of the field stimulation-evoked responses. @entity3159 (0.1-1 microM) suppressed the second phase but minimally affected the initial phase. Both phases were suppressed by @entity3897 (0.1-1 microM) and potentiated by @entity2607 (5 microM). dTC (0.5-20 microM) did not suppress either phase but potentiated the second phase. @entity1617 (0.28-280 microM) produced a contraction, which was reduced by @entity3897 but was little affected by either @entity9856 or @entity4524 . These results suggest that at the postsynaptic site of the neuromuscular junction in this tissue the sympathetic process activates the smooth muscle through two different types of receptor; one is non-noradrenergic and the other is an alpha-adrenoreceptor. In addition, a cholinergic process also activates the smooth muscle through muscarinic receptors.
