Metabolism and actions of ADP-riboses in coronary arterial smooth muscle. Adv Exp Med Biol 1997;419:437-41
Date
01/01/1997Pubmed ID
9193686DOI
10.1007/978-1-4419-8632-0_56Scopus ID
2-s2.0-0030945569 (requires institutional sign-in at Scopus site) 19 CitationsAbstract
The present study examined the metabolism of ADP-ribose (ADPR) and cyclic ADP-ribose (cADPR) in small bovine coronary arterial homogenates and characterized the effects of these nucleotides on the activity of potassium (K+) channels in coronary smooth muscle cells. ADPR and cADPR were produced from NAD+ (1mM) by homogenates from small bovine coronary arteries. The conversion rate was 2.81 +/- 0.19 nmol/min/100 micrograms protein for ADPR and 1.37 +/- 0.03 nmol/min/100 micrograms protein for cADPR. In patch clamp experiments, ADPR produced a concentration-dependent increase in the activity of a calcium activated K (Kca) channel in inside-out membrane patches of coronary arterial smooth muscle cells at concentrations of 0.1, 1 and 10 microM. The open state probability (NPo) of Kca channel was maximally increased 5-fold at a concentration of 10 microM. cADPR reduced the activity of Kca channel at concentrations of 1 and 10 microM. The NPo was decreased by 45% and 75%, respectively. The results indicate that there is an enzymatic pathway in the coronary arterial smooth muscle to produce ADPR and cADPR. These nucleotides may play a role in the control of coronary vascular tone by altering the activity of the Kca channel in vascular smooth muscle cells.
Author List
Li P, Zou AP, Campbell WBAuthor
William B. Campbell PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Adenosine Diphosphate RiboseAnimals
Cattle
Coronary Vessels
Cyclic ADP-Ribose
Electrophysiology
Ion Channel Gating
Large-Conductance Calcium-Activated Potassium Channels
Muscle, Smooth, Vascular
NAD
Potassium Channels
Potassium Channels, Calcium-Activated
Vasodilator Agents
