Schaumloffel V, Pugh V, Bealer S L
Department of Physiology and Biophysics, University of Tennessee, Memphis 38163.
Circ Shock. 1990 Jun;31(2):193-202.
The effect of electrolytic ablation of the periventricular tissue surrounding the anteroventral third ventricle (AV3V-X) of the rat brain on vascular compensation during prolonged hypotensive hemorrhage was determined. Anesthetized AV3V-X and control-operated (Cont) animals were subjected to a modified Wigger's hemorrhagic shock protocol. Maximum bled volume (MBV) was significantly lower in AV3V-X rats (2.74 +/- 0.14 ml/100 g BW) compared with control animals (3.51 +/- 0.16 ml/100 g BW). Pretreatment with the nonspecific alpha-adrenergic antagonist phentolamine (2.74 +/- 0.16 ml/100 g BW) or with the alpha 1-adrenergic antagonist prazosin (2.85 +/- 0.17 ml/100 g BW) reduced MBV in Cont rats, but did not attenuate MBV in AV3V-X animals (phentolamine: 2.33 +/- 0.17 ml/100 g BW; prazosin: 2.4 +/- 0.2 ml/100 g BW). In addition, maximum vasoconstriction was maintained for a significantly shorter period of time in AV3V-X (11.8 +/- 2.5 min) compared with Cont (30.8 +/- 10.5 min). These findings suggest that AV3V-X results in a deficit of alpha 1-adrenoreceptor activation during prolonged hypotension.
确定大鼠脑腹侧前第三脑室（AV3V-X）周围室周组织的电解消融对长时间低血压性出血期间血管代偿的影响。对麻醉的AV3V-X组和假手术对照组（Cont）动物实施改良的维格斯失血性休克方案。与对照动物（3.51±0.16 ml/100 g体重）相比，AV3V-X大鼠的最大出血量（MBV）显著更低（2.74±0.14 ml/100 g体重）。用非特异性α-肾上腺素能拮抗剂酚妥拉明（2.74±0.16 ml/100 g体重）或α1-肾上腺素能拮抗剂哌唑嗪（2.85±0.17 ml/100 g体重）预处理可降低Cont组大鼠的MBV，但对AV3V-X组动物的MBV无减弱作用（酚妥拉明：2.33±0.17 ml/100 g体重；哌唑嗪：2.4±0.2 ml/100 g体重）。此外，与Cont组（30.8±10.5分钟）相比，AV3V-X组的最大血管收缩维持时间显著更短（11.8±2.5分钟）。这些发现表明，AV3V-X导致长时间低血压期间α1-肾上腺素能受体激活不足。
