Effect of strychnine on the contractile response of rat vas deferens

Strychnine at concentrations of 0.1 approximately 1.0 microM induced supersensitivity of rat vas deferens to alpha-agonists but not to other stimulants. Strychnine-treatment resulted in an increase in the number of alpha-adrenoceptors, determined by measuring the binding of [3H]prazosin. Glycine did not have any significant effect on the contracture and did not antagonize the action of strychnine. Thus, specific supersensitivity of alpha-adrenergic system was induced by treatment with low concentrations of strychnine.