Effects of Calcium and Potassium Channel Blockers on Local Anesthetics-Induced Relaxation in Rat Thoracic Aortic Rings.
10.4097/kjae.1995.28.3.376
- Author:
Hyun Gu KIM
1
;
Sung Sik PARK
;
Jin Woong PARK
Author Information
1. Department of Anesthesiology, Kyungpook National University, College of Medicine, Taegu, Korea.
- Publication Type:Original Article
- Keywords:
Local anesthetics;
Calcium channel blockers;
Potassium channel blockers;
Aortic rings
- MeSH:
Anesthetics, Local;
Animals;
Aorta, Thoracic;
Bupivacaine;
Calcium Channel Blockers;
Calcium Channels;
Calcium*;
Diltiazem;
Lidocaine;
Nifedipine;
Potassium Channel Blockers*;
Potassium Channels*;
Potassium*;
Rats*;
Relaxation*;
Sodium;
Tea;
Tetracaine;
Tetraethylammonium;
Vasodilation;
Verapamil
- From:Korean Journal of Anesthesiology
1995;28(3):376-384
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
This study was designed to evaluate the effects of calcium and potassium channel blockers on local anesthetics-induced vascular relaxation of isolated rat thoracic aorta. In the presence of lidocaine and bupivacaine, the aortic rings previously contracted with phenylephrine(10(-4)M) were slightly contracted at the beginning of the administration of local anesthetics. But in the presence of tetracaine, aortic rings were not contracted at the beginnings. Verapamil, diltiazem and nifedipine in concentration of 10(-9)M to 10(-5)M produced cumulative concentration-dependent vasorelaxation significantly in the aortic rings previously contracted with phenylephrine(10(-4)M). In the presence of lidocaine, bupivacaine and tetracaine, verapamil, diltiazem and nifedipine in concentration of 10(-9)M to 10(-5)M caused dose-dependent vasorelaxation in aortic rings significantly. Tetraethylammonium HCl(TEA) in concentration of 10(-9)M to 10(-5)M did not produce dose-dependent vasorelaxation but slight contraction showed at the beginning of the administration. In the presence of lidocaine, bupivacaine, TEA in concentration of 10(-9)M to 10(-5)M did not produce vasorelaxation remarkably. But in the presence of tetracaine, TEA in concentration of 10(-9)M to 10(-5)M produced cumuIative concentration-dependent vasorelaxation significantly. These findings suggest that local anesthetics, especially tetracaine, which interact with calcium and potassium channel bleckers, lead to blockade of the sodium and calcium channels as well as potassium channels.