Takahashi H, Okabayashi H, Matsuzawa M, Suga K, Ikegaki I, Yoshimura M, Ijichi H
Second Department of Medicine, Kyoto Prefectural University of Medicine, Japan.
Cardiovasc Res. 1987 Jun;21(6):439-46. doi: 10.1093/cvr/21.6.439.
To investigate the effect of inhibition of cerebral Na+, K+-ATPase on cardiovascular regulation ouabain was injected into the lateral ventricle or the posterior hypothalamus in either conscious or urethane anaesthetised, deoxycorticosterone-salt hypertensive (DOCA) and sham operated (sham) rats. Ouabain injected intracerebroventricularly produced dose dependent vasopressor responses and tachycardia in the conscious rat; the magnitude of the pressor response was consistently larger in DOCA than in sham rats. In anaesthetised rats the pressor responses were accompanied by corresponding increases in abdominal sympathetic nerve activity. Thus the magnitude of the pressor responses, tachycardia, and the increases in nerve activity was again significantly greater in DOCA than in sham rats. Intrahypothalamic injections of ouabain produced pressor responses that were accompanied by consistent increases in both heart rate and abdominal sympathetic nerve activity in anaesthetised rats. In contrast to the intracerebroventricular injections the percentage increases from baseline blood pressure were significantly greater in sham than in DOCA rats at 5 min after injection. These results indicate that the centrally induced vasopressor response to ouabain, via the periventricular or bulbospinal system or both, is increased in DOCA-salt hypertensive rats whereas the pressor mechanism via the posterior hypothalamus is suppressed in DOCA rats.
为研究抑制脑钠钾ATP酶对心血管调节的影响，将哇巴因注入清醒或乌拉坦麻醉的脱氧皮质酮盐性高血压（DOCA）大鼠及假手术（sham）大鼠的侧脑室或下丘脑后部。清醒大鼠脑室内注射哇巴因可产生剂量依赖性的升压反应和心动过速；DOCA大鼠的升压反应幅度始终大于假手术大鼠。在麻醉大鼠中，升压反应伴随着腹部交感神经活动相应增加。因此，DOCA大鼠的升压反应幅度、心动过速及神经活动增加程度再次显著大于假手术大鼠。下丘脑内注射哇巴因在麻醉大鼠中产生升压反应，同时伴有心率和腹部交感神经活动持续增加。与脑室内注射不同，注射后5分钟时，假手术大鼠的血压较基线升高的百分比显著大于DOCA大鼠。这些结果表明，DOCA盐性高血压大鼠通过脑室周围或延髓脊髓系统或两者对哇巴因产生的中枢性升压反应增强，而DOCA大鼠通过下丘脑后部的升压机制受到抑制。
