Hemodynamic effects of corticotropin releasing hormone in the anesthetized cynomolgus monkey.
Right atrial bolus administration of rat/human corticotropin releasing hormone (r/hCRH) at a dose of 90 micrograms/kg to anesthetized cynomolgus monkeys caused a dramatic and prolonged fall in both the peripheral vascular resistance (48% reduction) and mean systemic blood pressure (36% reduction). An associated tachycardia could be blocked with prior propranolol administration and thus was probably reflexic. A mean 43 and 37% increase in the flow of the superior mesenteric and common iliac arteries, respectively, was demonstrated with electromagnetic flow probes. These changes were associated with a concomitant 38 and 40% diminution in the respective vascular resistance. Similar blood flow changes were noted in the carotid artery, however, these were of a much shorter duration. None of these changes occurred in placebo-treated animals. Plasma adrenocorticotropic hormone and cortisol concentrations were elevated basally and throughout the procedure and were similar in the experimental and control groups, suggesting maximal activity of the hypothalamic-pituitary-adrenal axis. Plasma renin activity, however, gradually increased in the r/hCRH-treated animals, probably as a result of the systemic hypotension. We speculate that CRH or a CRH-like substance may function as a paracrine hormone modulating local blood vessel tone and may be important in directing blood flow during stress and injury. The vasoactive properties of exogenous r/hCRH may be of clinical use in man.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D007700:Kinetics; D008252:Macaca fascicularis; D008297:Male; D013318:Stroke Volume / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D003346:Corticotropin-Releasing Hormone