Effect of desipramine on the depolarized isolated renal artery

Abstract

Depolarization of the isolated renal artery of the rat by a potassium-rich solution caused a triphasic response. The artery contracted submaximally then relaxed partially, this relaxation being followed by a slowly developing contracture. Desipramine reduced the height of the initial contraction, increased the relaxation and reduced the contracture. The latter action was antagonized by increasing the calcium ion concentration of the depolarizing solution. Calcium caused a contraction of the depolarized artery and the contraction was reduced by the drug. The results suggest that the relaxation of the depolarized artery produced by desipramine may be due to interference with the action of calcium in initiating and maintaining a contraction of the arterial smooth muscle.