Badoer E, McKinley M J, Oldfield B J, McAllen R M
Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Vic., Australia.
Brain Res. 1993 May 7;610(2):216-23. doi: 10.1016/0006-8993(93)91403-f.
The protein, Fos, detected immunohistochemically, was used to identify neurons in the brain that were activated after hemorrhage in the conscious rat. Spinally projecting neurons in the paraventricular nucleus (PVN) and rostral ventrolateral medulla (RVLM) were identified by the presence of rhodamine-labeled latex beads which had been previously injected into the upper thoracic spinal cord. On the experimental day, conscious rats underwent either (1) withdrawal of 4 ml of blood from a carotid cannula (n = 8) which reduced mean arterial pressure from 96.6 +/- 2.7 to 42.7 +/- 7.1 mmHg, (2) withdrawal of 2 ml of blood (n = 4) which did not affect mean arterial pressure. Animals that were not hemorrhaged were used as controls (n = 6). After the 4 ml hemorrhage, dense concentrations of Fos-positive cell nuclei were found in the lamina terminalis, supraoptic nuclei (SON), PVN and in the medulla. In contrast, the density of Fos-positive cells in 2 ml-hemorrhaged rats was not different from controls except in the SON and in the medial PVN in 2 of 4 rats. After the 4 ml hemorrhage 14.4 +/- 1.2% of the spinally projecting neurons in the PVN and 22.7 +/- 6.1% in the RVLM expressed Fos (P < 0.001 compared to control). After the 2 ml hemorrhage the proportion was 12.2 +/- 3.1% in the PVN (P < 0.001 compared control) but only 5.4 +/- 2.2% in the RVLM (P > 0.05 compared to control). The results suggest that spinally projecting neurons in the PVN and RVLM participate in the reflex responses to hemorrhage.(ABSTRACT TRUNCATED AT 250 WORDS)
通过免疫组织化学检测到的Fos蛋白，被用于识别清醒大鼠出血后大脑中被激活的神经元。通过先前注入上胸段脊髓的若丹明标记乳胶珠来识别室旁核（PVN）和延髓头端腹外侧区（RVLM）中向脊髓投射的神经元。在实验当天，清醒大鼠接受以下操作之一：（1）从颈动脉插管抽取4毫升血液（n = 8），这使平均动脉压从96.6±2.7降至42.7±7.1毫米汞柱；（2）抽取2毫升血液（n = 4），这对平均动脉压无影响。未进行出血操作的动物用作对照（n = 6）。4毫升出血后，在终板、视上核（SON）、PVN和延髓中发现了密集的Fos阳性细胞核。相比之下，2毫升出血大鼠中Fos阳性细胞的密度与对照组无差异，除了4只大鼠中有2只的SON和内侧PVN。4毫升出血后，PVN中14.4±1.2%的向脊髓投射神经元和RVLM中22.7±6.1%的神经元表达Fos（与对照组相比，P < 0.001）。2毫升出血后，PVN中的比例为12.2±3.1%（与对照组相比，P < 0.
