Baroreceptor influences on plasma atrial natriuretic peptide (ANP): sinoaortic denervation reduces basal levels and the response to an osmotic challenge.
The objective of these studies was to investigate baroreceptor/osmotic interactions by determining the effect of sinoaortic denervation (SAD) on the ANP response to a hypertonic saline challenge in conscious rats. A time course study showed that there was a rapid increase in plasma ANP in response to iv hypertonic saline. The peak effect was at 5 min, a 3-fold increase (P less than .01). Baroreceptor denervation produced significant decreases in basal ANP levels and osmotic induced release (P less than 0.01). Plasma ANP increased from 25 +/- 3.2 to 136.8 +/- 28 in the sham-operated rats and from 11.8 +/- 2.6 to 30.8 +/- 4.6 in the SAD. Plasma sodium was the same in the 2 groups, and there was no change in atrial ANP content. Blood pressure was elevated in the denervated animals; however, the pressor response to the hypertonic challenge was not different from the controls. These results suggest that the baroreceptor system may have important influences on cardiovascular/hormonal regulation.
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000097:blood*; D003714:Denervation; D006325:Heart Atria / Q000378:metabolism; D006400:Hematocrit; D008297:Male; D009206:Myocardium / Q000378:metabolism; D011311:Pressoreceptors / Q000502:physiology*; D051381:Rats; D012849:Sinoatrial Node / Q000502:physiology*; D012964:Sodium / Q000097:blood
D009320:Atrial Natriuretic Factor; D012964:Sodium