Gören M Z, Akici A, Berkman K, Onat F
Department of Pharmacology and Clinical Pharmacology, Marmara University School of Medicine, Istanbul, Turkey.
Pharmacology. 2000 Nov;61(4):257-62. doi: 10.1159/000028410.
The nuclei of hypothalamus and amygdala have been shown to be involved in the central cardiovascular homeostasis. Recent studies suggest that glutamate-containing neurons have an important role in the regulation of the central cardiovascular function. In this study, we demonstrate the roles of the central nucleus of the amygdala and the paraventricular nucleus of the amygdala and the paraventricular nucleus or the dorsomedial nucleus of the hypothalamus in N-methyl-D-aspartate (NMDA) induced blood pressure and heart rate changes in conscious Sprague-Dawley rats. Intracerebroventricular or parenchymal injections of NMDA evoke increases in arterial pressure. The NMDA-induced elevations in blood pressure are more prominent when NMDA is administered into the dorsomedial nucleus of the hypothalamus. Microinjections of NMDA into the dorsomedial hypothalamus exert significant heart rate increases, whereas NMDA when administered into the paraventricular nucleus of the hypothalamus or into the central nucleus of the amygdala has no significant effect on the heart rate. The dorsomedial nucleus of the hypothalamus is found to be the most effective site in this respect. The present study provides strong evidence for the tonic glutamatergic influence on blood pressure and heart rate via NMDA receptors located within the dorsomedial nucleus and to a lesser extent via those located within the paraventricular nucleus of the hypothalamus.
下丘脑和杏仁核的核团已被证明参与中枢心血管稳态调节。最近的研究表明，含谷氨酸的神经元在中枢心血管功能调节中起重要作用。在本研究中，我们证明了杏仁核中央核、杏仁核室旁核以及下丘脑室旁核或背内侧核在N-甲基-D-天冬氨酸（NMDA）诱导的清醒斯普拉格-道利大鼠血压和心率变化中的作用。脑室内或实质内注射NMDA可引起动脉压升高。当NMDA注入下丘脑背内侧核时，其诱导的血压升高更为显著。向背内侧下丘脑微量注射NMDA可使心率显著增加，而当NMDA注入下丘脑室旁核或杏仁核中央核时，对心率无显著影响。在这方面，下丘脑背内侧核被发现是最有效的部位。本研究提供了强有力的证据，表明通过位于背内侧核内的NMDA受体以及在较小程度上通过位于下丘脑室旁核内的NMDA受体，谷氨酸能对血压和心率产生紧张性影响。
