AJP - Cell Physiology, Vol 232, Issue 3 128-C131, Copyright © 1977 by American Physiological Society
Effects of cadmium and lead on adrenergic neuromuscular transmission in the rabbit
G. P. Cooper and D. Steinberg
The effects of inorganic lead (PbCl2) and cadmium (DdCl2) on the pressor
response of rabbit saphenous arteries produced by sympathetic nerve
stimulation were examined. A 1- to 3-cm length of artery was removed,
placed in a bath containing mammalian Ringer solution, and perfused with
the same solution at a constant rate sufficient to maintain a 40-60 mmHg
perfusion pressure. Increases in perfusion pressure resulting from
electrical stimulation -f periarterial nerve endings were reduced or
completely blocked by the addition of 5-20 muM lead or cadmium to the
bathing solution for a period of 15-30 min. Responses to norepinephrine or
to direct electrical stimulation of the muscle remained relatively
unaffected. During lead or cadmium blockade, the response to nerve
stimulation could be restored by a fourfold increase in calcium
concentration. It is concluded that lead and cadmium reduce the response to
sympathetic nerve stimulation primarily through an effect on presynaptic
nerve terminals.
