Changes in endogenous ANP, renal function, and hemodynamics during acute right ventricular pacing in anesthetized dogs

• Published in: Japanese Journal of Pharmacology Vol. 71; no. suppl.2; p. 288
• Main Authors: Yoneda, Hikaru, Yamada, Hiroshi, Yano, Koji, Nishiyama, Shinsuke, Naito, Kazuaki
• Format: Journal Article
• Language: Japanese; English
• Published: The Japanese Pharmacological Society 1996
• ISSN: 0021-5198; 1347-3506
• DOI: 10.1016/S0021-5198(19)37393-7

Changes in concentration of plasma ANP, renal function, and hemodynamics during acute right ventricular pacing were investigated in closed-chest anesthetized dogs. Dogs were paced via the right ventricle at a rate of 200 or 250 bpm for 180 min. Both 200 and 250 bpm pacing induced increases in plasma ANP and urinary excretion of cGMP(UcGMPV). The changes in plasma ANP and UcGMPV during 250 bpm pacing were significantly higher than those during 200 bpm pacing. The increases in urinary excretion of sodium(UNaV) and urine volume(UV) during 250 bpm pacing were similar extent to increases in those during 200 bpm pacing. Cardiac output was decreased at the same extent by 200 and 250 bpm pacing. Slight and temporary decrease in renal blood flow(RBF) was observed by 200 bpm pacing, but the change was not significantly different from the change during 250 bpm pacing. Mean arterial pressure(MAP), left ventricular end-diastolic pressure(LVEDP), pulmonary arterial pressure(PAP), renal vascular resistance (RVR) and glomerular filtration rate(GFR) were not changed during 200 bpm pacing. MAP and RVR were decreased, and LVEDP and PAP were increased by 250 bpm pacing without altering RBF and GFR. In conclusion, 250 bpm pacing but not 200 bpm pacing induced an increase in the left ventricular pre-load. Increases in UNaV and UV during 250 bpm pacing were the same extent to those during 200 bpm pacing in which plasma ANP and UcGMPV were lower. The results indicate that some mechanisms counteract to an inhibitory effect on Na reabsorption of endogenous ANP under 250 bpm pacing condition.