|
KMID : 0360419940300030313
|
|
Korean Journal of Pharmacology
1994 Volume.30 No. 3 p.313 ~ p.319
|
|
|
Amiloride-sensitive Na+ Channels Are Not Involved in the Cardiovascular Responses to Increased Na+ Concentration in Cerebrospinal Fluid
|
|
Kook Hyun
Kim Jae-Ha
Baik Yung-Hong
|
|
|
Abstract
|
|
|
|
This study was undertaken to investigate the relationship between the Na+ channels of the cardiovascular regulation center and the responses to increased Na+ concentration in the cerebrospinal fluid (CSF), by observing the effects of icv administration of the agents affecting Na+ transport. Icv infusion of 200㎕ of 1 M NaCl produced hypertension and bradycardia in the urethane-anesthetized rabbit, and the bradycardia was inhibited and reversed to tachycardia by vagotomy. Amiloride, a Na+ transport inhibitor, produced hypertension and bradycardia, which were not altered by vagotomy, and it did not affect the NaCl-induced responses. Benzamil, a derivative of amiloride with higher specificity, neither produced any cardiovascular effects by itself, nor affected the NaCl-induced responses. In vagotomized rabbits, icv amiloride reversed the NaCl-induced tachycardia to a bradycardia, but the bradycardiac effect was not altered by pretreating with NaCl. This study showed that although amiloride and benzamil slightly differ in their cardiovascular action, neither of them did affect the NaCl-induced responses. We suggest that the Na+ channels which are sensitive to amiloride or benzamil in the cardiovascular regulation center are not involved in the NaCl-induced response.
|
|
|
KEYWORD
|
|
|
Amiloride, Benzamil, Na+channel, Cerebrospinal fluid
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
|
|