Acute Pressor Effects of Intra-Arterial Cadmium and Mercuric Ions In Anesthetized Rats.

Abstract

SummaryFrom 10 to 40 μg of intraarterial cadmium ion per 100 g body weight reproducibly raised the diastolic pressure of anesthetized rats an average of 25 mm Hg. The effect was nearly maximal within one minute and had decreased by half within 8 minutes. Larger doses of cadmium were transiently depressor. The pressor effect was not immediately inhibited by adrenalectomy, nephrectomy, or autonomic blockade. Zinc produced no similar pressor response, but mercury did. The minimum effective dose of mercuric ion was larger, but moderate doses were more pressor, and large doses were not depressor. Vanadyl, silver, barium, and cupric ions also had some pressor activity. The pressor effect of cadmium was immediately reversed by a chelating agent and more slowly reversed by an anti-hypertensive agent thought to act locally on vascular smooth muscle.