[Effect of hypertonic NaCl solution on arterial pressure compensation after hemorrhage in rats].
Rats were bled within 5 min in lowering mean arterial pressure (MAP) to 25 mmHg and were subsequently infused intravenously with hypertonic (7.5% NaCl) or normal saline in a volume equal to 10% of the amount of the lost blood. Intravenous infusion of hypertonic saline significantly facilitated posthemorrhagic recovery of MAP, which was markedly attenuated by 6-hydroxydopamine or Captopril. When these two drugs were used together, the attenuation effect was complete. While hypertonic saline significantly increased plasma Na+ concentration, normal saline only gave rise to a decrease. Intracerebroventricular injection of hypertonic NaCl solution also facilitated the recovery of MAP significantly. These results suggest that after hemorrhage increased plasma Na+ concentration following i.v. of a small amount of hypertonic saline may act on the central nervous system and activate sympathetic nervous system and renin angiotensin system to facilitate a rapid recovery of MAP.
Pan
J Y
JY
Department of Physiology, Sun Yat-Sen University of Medical Sciences, Guangzhou.
Dong
X H
XH
Liu
J L
JL
Song
X L
XL
Hou
H C
HC
Zhan
C Y
CY
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D007262:Infusions, Intravenous; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012084:Renin-Angiotensin System / Q000187:drug effects; D012462:Saline Solution, Hypertonic / Q000494:pharmacology / Q000627:therapeutic use*; D012771:Shock, Hemorrhagic / Q000188:drug therapy*; D013564:Sympathetic Nervous System / Q000187:drug effects
D012462:Saline Solution, Hypertonic