Effect of heating on vascular reactivity in rat mesenteric arteries. 1998

M P Massett, and S J Lewis, and J N Bates, and K C Kregel
Department of Exercise Science, The University of Iowa, Iowa City, Iowa 52242, USA.

Vasoconstriction in the viscera is one of the primary cardiovascular adjustments to heating. Local temperature can influence vascular responsiveness to catecholamines and sympathetic nerve activity. Therefore, we hypothesized that heating would alter vascular reactivity in rat mesenteric arteries. Concentration-response curves to norepinephrine, phenylephrine, potassium chloride (KCl), calcium, acetylcholine, and sodium nitroprusside were obtained in vascular ring segments from rat mesenteric arteries at 37 and 41 degrees C. In some rings, basal tension increased slightly during heating. Heating to 41 degrees C did not alter the contractile responses to norepinephrine in endothelium-intact or -denuded rings but augmented the responses to KCl and calcium in endothelium-intact rings. The potentiating effect of heating on the responses to KCl and calcium was eliminated after endothelium removal. In contrast, the relaxant responses to acetylcholine and sodium nitroprusside were significantly attenuated at 41 degrees C. Collectively, these results demonstrate that heating alters vascular reactivity in rat mesenteric arteries. Furthermore, these data imply that heating reduces the ability of vascular smooth muscle to relax, possibly due to a decrease in sensitivity to nitric oxide.

UI MeSH Term Description Entries
D008297 Male Males
D008638 Mesenteric Arteries Arteries which arise from the abdominal aorta and distribute to most of the intestines. Arteries, Mesenteric,Artery, Mesenteric,Mesenteric Artery
D009119 Muscle Contraction A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments. Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009126 Muscle Relaxation That phase of a muscle twitch during which a muscle returns to a resting position. Muscle Relaxations,Relaxation, Muscle,Relaxations, Muscle
D009131 Muscle, Smooth, Vascular The nonstriated involuntary muscle tissue of blood vessels. Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D009569 Nitric Oxide A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP. Endogenous Nitrate Vasodilator,Mononitrogen Monoxide,Nitric Oxide, Endothelium-Derived,Nitrogen Monoxide,Endothelium-Derived Nitric Oxide,Monoxide, Mononitrogen,Monoxide, Nitrogen,Nitrate Vasodilator, Endogenous,Nitric Oxide, Endothelium Derived,Oxide, Nitric,Vasodilator, Endogenous Nitrate
D002118 Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D004730 Endothelium, Vascular Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components. Capillary Endothelium,Vascular Endothelium,Capillary Endotheliums,Endothelium, Capillary,Endotheliums, Capillary,Endotheliums, Vascular,Vascular Endotheliums
D006358 Hot Temperature Presence of warmth or heat or a temperature notably higher than an accustomed norm. Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D006439 Hemodynamics The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM. Hemodynamic

Related Publications

M P Massett, and S J Lewis, and J N Bates, and K C Kregel
March 2001, American journal of physiology. Heart and circulatory physiology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
October 2006, Pflugers Archiv : European journal of physiology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
April 1984, Japanese journal of pharmacology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
February 2009, Anesthesia and analgesia,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
January 1996, Methods and findings in experimental and clinical pharmacology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
April 2003, Journal of cardiovascular pharmacology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
April 1997, Canadian journal of physiology and pharmacology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
March 1998, Journal of anesthesia,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
May 2006, Basic & clinical pharmacology & toxicology,
M P Massett, and S J Lewis, and J N Bates, and K C Kregel
May 1990, Anesthesia and analgesia,
Copied contents to your clipboard!