search
for
 About Bioline  All Journals  Testimonials  Membership  News


Nigerian Journal of Physiological Sciences
Physiological Society of Nigeria
ISSN: 0794-859X
Vol. 17, No. 1-2, 2002, pp. 16-19
Bioline Code: np02003
Full paper language: English
Document type: Research Article
Document available free of charge

Nigerian Journal of Physiological Sciences, Vol. 17, No. 1-2, 2002, pp. 16-19

 en VITAMIN ENHANCES RELAXATION OF RAT AORTIC RINGS INDUCED BY K+ AND Mg2+
R. E. ETTARH AND S. A. ADIGUN

Abstract

This study was designed to determine the effects of administration the effects of administration of vitamin C on the relaxation of vascular smooth muscle to K+ and Mg2+. The experiments were performed in two groups of Sprague-Dawley rats aged 6 weeks. Both control and test groups received rat chow and normal drinking water. In addition, the test group received vitamin C (100mg/kg/day) by intragastric administration for 8 weeks. At the end of this period aortic rings were obtained from both groups and used for isometric recordings. The relaxation responses to K+ and Mg2+ after precontraction with noradrenaline (10-7M) were higher in the vitamin C-treated group compared with the control group. There was no difference in the relaxation responses to Mg2+ following K+ (40 mM) precontraction in the two groups. The enhanced relaxation to K+ in vitamin C rats suggests an increase in vascular Na+ -K+ ATPase activity. The increase in relaxation to Mg2+ follow NA precontraction, which was not observed with K+ precontraction, suggests that vitamin C enhances the mechanism of Mg2+-induced relaxation following receptor-mediated, but not depolarization-dependent contraction.

Keywords
Vitamin C, Potassium, Magnesium, Vascular reactivity

 
© Copyright 2002 - Physiological Society of Nigeria

Home Faq Resources Email Bioline
© Bioline International, 1989 - 2024, Site last up-dated on 01-Sep-2022.
Site created and maintained by the Reference Center on Environmental Information, CRIA, Brazil
System hosted by the Google Cloud Platform, GCP, Brazil