Atrial natriuretic peptide infusion causes vasoconstriction after autonomic blockade in conscious dogs

Research output: Contribution to journalArticleResearchpeer-review

20 Citations (Scopus)

Abstract

Many studies have shown that atrial natriuretic peptide (ANP) reduces mean arterial pressure (MAP) in conscious animals by lowering cardiac output (CO) with no change or even increased total peripheral resistance (TPR). Because ANP is thought to be a vasodilator, the lack of fall in TPR in conscious animals is generally considered to be due to autonomic reflex increases in vascular resistance. In the present study in conscious, trained, chronically instrumented dogs (n = 7), we measured hemodynamic and renal excretory responses to 30-min infusions of α-human ANP (αhANP; 25, 50, and 100 ng·kg-1·min-1) in the presence and absence of autonomic nervous system blockade using the ganglion blocking agent pentolinium. In the absence of blockade, MAP and CO fell, whereas TPR rose with αhANP infusions, but these changes did not reach significance. There were significant increases in renal vascular resistance (RVR; 16-25%) and mesenteric vascular resistance (MVR; 14-40%). During autonomic nervous system blockade, αhANP caused dose-related reductions in MAP (7-12%), due to falls in CO (13-34%). Remarkably, the absence of autonomic reflex responses exposed substantial dose-related increases in TPR (5-33%). Autonomic blockade did not alter the ANP-induced increases in MVR but did abolish the rises in RVR. In summary, ANP caused vasoconstriction in mesenteric vasculature and substantial vasoconstriction in other nonrenal areas, independent of autonomic reflexes.

Original languageEnglish
JournalAmerican Journal of Physiology
Volume259
Issue number4 28-4
Publication statusPublished - 1990
Externally publishedYes

Keywords

  • autonomic reflexes
  • cardiac output
  • ganglion blockade
  • mesenteric vascular resistance
  • pentolinium
  • renal vascular resistance
  • renin
  • total peripheral resistance
  • vasopressin

Cite this