一氧化氮合酶和一些神经递质（神经肽）在自发性高血压大鼠孤束核的分布

用ＮＡＤＰＨ－ｄｉａｐｈｏｒａｓｅ组织化学和免疫细胞化学方法，观察和比较了一氧化氮合酶、酪氨酸羟化酶、５－羟色胺、Ｐ物质和亮氨酸脑啡肽在自发性高血压大鼠和正常对照大鼠孤束核的分布。结果显示，孤束核内一氧化氮合酶阳性细胞在高血压组少于对照组，有显著性差异（Ｐ＜０．０５）。孤束核Ｐ物质和亮氨酸脑啡肽免疫阳性物在高血压组多于对照组；酪氨酸羟化酶免疫阳性物高血压组少于对照组；５－羟色胺免疫阳性物在两组的分布无明显差异。提示一氧化氮在孤束核是一种降压性局部神经调质，与其在心血管系统的降压作用一致。中枢Ｐ物质含量的异常增加可能是高血压发病的原因之一。孤束核脑啡肽含量的异常增加与高血压的形成有关，痛觉和高血压之间可能存在一些共同的发生机制。酪氨酸羟化酶在高血压组降低提示孤束核内酪氨酸羟化酶对维持正常血压发挥重要作用．孤束核内５－羟色胺与血压调节无关。

DISTRIBUTION OF NOS-NEURONS AND NEUROTRANSMITTERS (OR PEPTIDES) IN THE SHR NUCLEUS OF SOLITARY TRACT

The distribution of nitric oxide synthase (NOS)-containing neurons and tyrosine hydroxylase (TH), Serotonin(5-HT),substance P (SP) and L-enkephalin (L-ENK) in the spontaneously hypertensive rats (SHR ) and Wistar Kyoto rats (WKY) were observed by using NADPH diaphorase histochemistry and immunocytochemistry. The data showed that NOSpositive cells of SHR were less than WKY. There were significant difference between SHR and WKY (P<0. 05 ). In nucleus of solitary tract(NTS) SP and L-ENK immuno-positive products of SHR were more than WKY: but TH immuno-positive product of SHR was less than WKY; 5-HT immuno-positive product was not different in SHR and WKY. These results suggest that NO may be a localized neuromodulator for blood pressure descending in NTS, which is assumed to possess the function of lowering blood pressure in cardiovascular system. An abnormal increase of SP-product in NTS may be one of the cause of inducing hypertension. An abnormal increase of L-ENK in NTS may be involved by incidence of hypertension and have a common reason between pain and hypertension. The declining of TH in NTS of WKY suggest that TH may play an important role in the maintenance of normal blood pressure. 5-HT in NTS may have nothing with in regulating blood pressure.