To elucidate one of the effect of piperine on the peripheral sympathetic nervous system, influence of piperine upon the contractile action of norepinephrine, methoxamine and tyramine as well as uptake and release of $[^{3}H]-norepinephrine$ has been investigated in naive and chronic piperine-treated vas deferens of rats. $pA_2$ value for ${alpha}_1-adrenoceptor$ of phentolamine was significantly increased. Chronic piperine-treated group was markedly shown increased efflux of $[^{3}H]-norepinephrine$ and muscular tension, but was not affected the neuronal up-take and release of $[^{3}H]-norepinephrine$. It can be concluded that potentiation of the effect of norepinephrine by acute and chronic piperine treated group may be due to the change of affinity of ${alpha}_1-adrenoceptor$, and partly due to possible modification of storage mechanism.