Affiliation:
1. Department of Physiology, University of Virginia School of Medicine, Charlottesville, Virginia 22901
Abstract
Two to 4 m
M
5'-adenosine monophosphate (AMP) caused a 28% inhibition of the ATPase activity of a crude "fibrillar" contractile protein preparation isolated from porcine vascular smooth muscle. This effect was absent in highly purified Ca
2+
-insensitive actomyosin extracted from carotid arteries as well as a Ca
2+
-dependent actomyosin preparation. Inorganic phosphate (P
1
) caused no inhibition of ATPase activity in either actomyosin preparation, but 4 m
M
P
1
produced a slight depression in ATP hydrolysis of the crude fibrillar proteins. Superprecipitation of actomyosin remains unaffected by additions of either 4 m
M
P
1
or 4 m
M
AMP to the purified protein solutions. The effects of P
1
and AMP in combination were additive in the fibrillar system. However, the combination of the two agents had no effect on the ATPase activity of the two actomyosin preparations. These results indicate that concentrations of P
1
and AMP which might be produced under physiological conditions have no direct inhibitory action on the vascular smooth muscle actin-myosin interaction.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Cardiology and Cardiovascular Medicine,Physiology
Reference14 articles.
1. GUYTON A.C. Ross J.M. GABBIER O. JR. AND WALKER J.R.: Evidence for tissue oxygen demand as the major factor causing autoregulation. Circ Res 15: (suppl I):I-60-68 1964.
2. Control of smooth muscle actomyosin by phosphate and 5′AMP: Possible role in metabolic autoregulation
3. Control of precapillary sphincters and the mechanisms of circulation-metabolism coupling. In Proc 4th Int Congr Pharmacol, edited by R. Eigenmann. Philadelphia;HONIG C.R.;J. B. Lippincott Co.,1970
4. The Effects of Adrenaline and Glucose on the Content of High-Energy Phosphate Esters in Substrate-Depleted Vascular Smooth Muscle
5. Action du chlorure de potassium sur le metabolisme des esters phosphores et le tonus du muscle arteriel (carotide de bovide);DAEMERS-LAMBERT C;Angiologica,1964
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