Abstract
There is considerable interest in the antihypertensive potential of supplemental dietary calcium in salt-sensitive hypertension. Previously we reported that very high dietary calcium (4.0% vs. 0.4%) lowers mean arterial pressure in Dahl salt-sensitive (DS) hypertensive rats. However, we have recently observed that more moderate calcium supplementation (2.0% vs. 0.4%) increases mean arterial pressure in DS rats. To further evaluate the pressor action of 2.0% versus 0.4% calcium, we tested for effects of 2.0% calcium in female DS rats fed low (0.2%), moderate (1.0%), and high (2.7%) sodium and in Dahl salt-resistant (DR) rats fed high sodium from 6 to 12 weeks old (n = 10-13 rats per group). At 12 weeks, 2.0% calcium increased mean arterial pressure and the cardiac ventricular weight/body weight ratio in DS rats fed high sodium (p less than 0.05) but not in DS rats fed low or moderate sodium or in DR rats fed high sodium. Ganglionic blockade decreased mean arterial pressure in all groups but failed to abolish or attenuate the difference in mean arterial pressure between high sodium-fed DS rats on 2.0% and 0.4% calcium diets. In the same DS rats fed a high sodium diet, 2.0% calcium increased systemic pressor responsiveness to graded norepinephrine administration after ganglionic blockade. Thus, 2.0% supplemental calcium intake enhances salt-induced hypertension in DS rats. This prohypertensive action of 2.0% calcium is dependent on a critically high level of between 1.0% and 2.7% sodium in the diet.(ABSTRACT TRUNCATED AT 250 WORDS)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.