RT Journal Article
SR Electronic
T1 ANTAGONISM OF VASOCONSTRICTOR RESPONSES BY EXERCISE IN THE GRACILIS MUSCLE OF THE DOG
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 78
OP 85
VO 187
IS 1
A1 Burcher, Elizabeth
A1 Garlick, David
YR 1973
UL http://jpet.aspetjournals.org/content/187/1/78.abstract
AB Responses to lumbar sympathetic stimulation. and to intra-arterial injections of norepinephrine, vasopressin and angiotensin were elicited in the vascularly isolated dog gracilis muscle, perfused with blood at constant flow and by autoperfusion. Sympathetic stimulation was antagonized by exercise, the degree of inhibition being dependent on the level of exercise. Responses to norepinephrine, vasopressin and angiotensin were also antagonized by exercise, suggesting that the inhibition is nonspecific. A comparison of norepinephrine and sympathetic stimulation showed that sympathetic responses were significantly more reduced by exercise than responses to norepinephrine. This suggests either that endogenous and exogenous norepinephrine activate different populations of receptors, or more likely that during exercise there may be some inhibition to sympathetic neurotransmission in addition to the nonspecific inhibition of circulating vasoconstrictors. © 1973 by The Williams & Wilkins Company