Korean J Physiol Pharmacol.  1998 Feb;2(1):55-62.

Effects of alpha-, beta-adrenergic, and calcium channel blockers on renin- angiotensin system in perfused rat heart

• Park CG

Abstract

alpha-,beta-Adrenergics, and calcium channels were known to be related to inducing cardiac hypertrophy. Recently, it was reported that the cardiac renin-angiotensin system (RAS) was an important factor in ventricular hypertrophy. The present study was aimed to investigate the effects of alpha-, beta-adrenergic, and calcium channel blockers that might be involved in the regulation of cardiac RAS. The reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of renin gene in the perfused rat heart. Changes in angiotensin converting enzyme (ACE) activity and cyclic AMP (cAMP) content which were thought to play a role in inducing cardiac hypertrophy were measured in the perfused rat heart. The expression of renin gene was not only increased by isoproterenol with metoprolol-pretreatment but also increased by vasopressin treatment in the presence of calcium channel blocker, nifedipine or verapamil. Either prazosin alone or norepinephrine with prazosin-pretreatment significantly increased the ACE activity. However, isoproterenol with metoprolol-pretreatment significantly decreased the ACE activity. On the other hand, the ACE activity was not changed by vasopressin, nifedipine, or verapamil treatments. The content of cAMP was significantly increased by either isoproterenol or vasopressin treatment. According to these results, renin gene expression was associated with beta2-adrenoceptor and calcium channel. ACE activity was associated with alpha- and beta2- adrenoceptor. In conclusion, beta2-adrenoceptor was important in cardiac renin gene expression and ACE activity and alpha-, beta-adrenergic, and calcium channel blockers might be involved in the regulation of cardiac RAS in a complicated way.

Keyword

Ventricular hypertrophy; Renin-angiotensin system

MeSH Terms

Angiotensins*
Animals
Calcium Channel Blockers*
Calcium Channels*
Calcium*
Cardiomegaly
Cyclic AMP
Gene Expression
Hand
Heart*
Hypertrophy
Isoproterenol
Nifedipine
Norepinephrine
Peptidyl-Dipeptidase A
Prazosin
Rats*
Renin
Renin-Angiotensin System
Vasopressins
Verapamil
Angiotensins
Calcium
Calcium Channel Blockers
Calcium Channels
Cyclic AMP
Isoproterenol
Nifedipine
Norepinephrine
Peptidyl-Dipeptidase A
Prazosin
Renin
Vasopressins
Verapamil