Dilatory humoral adrenergic reactions of regional veins and arteries during systemic hypoxia and hypothermia.
In experiments on anesthetized cats, perfusion of neurally decentralized vessels in the gastrocnemius muscle and small intestine with constant flow of autoblood containing isoproterenol induced dilator reactions in arteries and veins. Against the background of hypoxic hypoxia, the reactions of arteries and veins in the gastrocnemius muscles and veins in small intestine attenuated, although the arterial reactions in the latter region did not change. Total hypothermia (30 degrees C) attenuated the dilator reactions in regional vessels. Under the combined action of hypoxia and hypothermia, the amplitudes of dilator reactions of muscle vessels and intestine veins were equal to the baseline values, although the responses of intestinal arteries were pronouncedly weakened. It is concluded that blood vessels in the gastrocnemius muscle and veins in the small intestine possess positive resistance to whole-body hypoxia and hypothermia.
Tabarov
M S
MS
Department of Visceral System Physiology, Institute of Experimental Medicine, Russian Academy of Medical Sciences, St. Petersburg.
Kudryashov
Yu A
YA
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D001158:Arteries / Q000503:physiopathology; D002415:Cats; D007035:Hypothermia / Q000503:physiopathology*; D000860:Hypoxia / Q000503:physiopathology*; D007421:Intestine, Small / Q000098:blood supply; D007545:Isoproterenol / Q000494:pharmacology; D018482:Muscle, Skeletal / Q000098:blood supply*; D009130:Muscle, Smooth / Q000098:blood supply*; D012039:Regional Blood Flow; D014664:Vasodilation / Q000187:drug effects*; D014680:Veins / Q000503:physiopathology
D000318:Adrenergic beta-Agonists; D007545:Isoproterenol