These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Chronic effects of vasopressin on plasma renin activity in sodium-restricted dogs.
    Author: Merrill DC, Cowley AW.
    Journal: Am J Physiol; 1986 Mar; 250(3 Pt 2):F460-9. PubMed ID: 3513620.
    Abstract:
    The effects of chronic (4 days) arginine vasopressin (AVP) infusion were studied in two separate groups of animals: normal Na-restricted dogs with intact renal nerves (n = 8) and renal-denervated Na-restricted dogs (n = 5). Volume expansion during AVP infusion was prevented in these studies with a sensitive servo-controlled cage-scale system. With intravenous AVP infusion (0.36 ng X kg-1 X min-1), plasma AVP levels increased from nearly 3 to 15 pg/ml, whereas total body weight remained unchanged from the control level. In renal-innervated dogs, plasma renin activity (PRA) decreased significantly (P less than 0.05) from control levels of 5.50 +/- 0.61 to an average level of 3.45 +/- 0.76 ng angiotensin I (ANG I) X ml-1 X h-1 on days 1 and 2 of AVP infusion. Thereafter, PRA tended to remain decreased on days 3 and 4, averaging 3.82 +/- 1.02 ng ANG I X ml-1 X h-1, but this was not statistically significant. Urinary Na excretion and balance, however, were not significantly altered during the 4-day AVP infusion period. In renal-denervated dogs, the rise of PRA with Na restriction was 50% that seen in normal dogs. In this group, a transient suppression of PRA was observed on day 1 of AVP infusion from 2.84 +/- 0.75 to 1.46 +/- 0.47 ng ANG I X ml-1 X h-1. Urinary Na excretion increased transiently with a small net Na loss of 4.9 +/- 1.3 meq on day 2 of AVP infusion. No significant changes occurred in average 24-h mean arterial pressure (MAP) in response to AVP in either group of dogs. Thus, in contrast to our previous observations in Na-replete dogs, elevations of plasma AVP within the physiological range result in suppression of PRA, but for periods of no longer than 1-2 days in Na-restricted dogs. This decrease of PRA occurred in the absence of measurable changes in MAP, total body weight, or plasma catecholamines. In addition, this transient AVP-induced suppression of PRA was only partially blunted by prior renal denervation. Finally, in the Na-restricted dog, AVP appears to have minimal or no long-term effects on urinary Na excretion.
    [Abstract] [Full Text] [Related] [New Search]