Role of the renal sympathetic nerve activity in determining salt sensitivity.

肾交感神经活动在确定盐敏感性中的作用。

• 批准号: 07670088
• 负责人: KANNAN Hiroshi
• 金额: $ 1.41万
• 依托单位: Miyazaki Medical College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07670088/
• 关键词: salt-sensitivity; renal sympathetic nerve activity; renal sodium excretion; vasopressin; cardiovascular regulation; rat; 心血管反応; ダール食塩感受性ラット; 食塩負荷; 意識下ラット

The mechanisms underlying salt-dependent hypertension are not entirely known. Renal sympathetic nerve activity (RSNA) has a direct effect on the control of renal blood flow, renin release and urinary sodium excretion.1.We have recorded RSNA in free-moving Dahl salt sensitive (DS) and salt-resistant (DR)-rats on a low NaCl diet.(1) Under resting conditions, two types of discharge patterns were seen, a grouped cardiac-related discharge (GD) and a non-grouped irregular discharge (NGD). The GD was inhibited by i.v.administration of phenylephrine chloride, while the NGD was not. Both GD and NGD were seen in DS and DR rats and both were completely abolished by i.v.administration of the ganglionic blocker, hexamethonium chloride.(2) l.c.v.infusion of hypertonic NaCl solution significantly increased arterial blood pressure and decreased RSNA compared with the resting levels in both Dahl-R and Dahl-S rats. However, the responsiveness of RSNA to NaCl did not differ in either group. Heart rate did not significantly change.(3) During 0.3 M NaCl infusion, water intake in Dahl-S rats was diminished compared with that in Dahl-R-rats.2.Next, using conscious Sprague-Dawley rats, we have examined responsiveness of RSNA in response to central salt loading. The inhibitory response of RSNA following i.c.v.administration of hypertonic NaCl solution were,(1) greatly attenuated under pentobarbital anesthesia.(2) enhanced in conscious rats not access to water.(3) observed in sinoaortic denervated (SAD) conscious rats.(4) significantly attenuated by pretreatment with vasopressin V_1 antagonist (OPC-21268, i.v.) but not V_2 antagonist (OCP-31260).

盐依赖型高血压的发病机制尚不完全清楚。肾交感神经活动(RSNA)直接影响肾血流量、肾素释放和尿钠排泄。1.我们在低盐饮食自由活动Dahl盐敏感(DS)和耐盐(DR)大鼠上记录到RSNA。(1)在安静状态下，观察到心脏相关放电(GD)和非分组不规则放电(NGD)两种类型的放电。静脉注射氯化苯肾上腺素可抑制GD，而NGD则不受抑制。DS和DR大鼠均可见GD和NGD，并可被神经节阻滞剂六甲基氯化铵完全阻断。(2)静脉注射高渗氯化钠溶液可显著升高Dahl-R和Dahl-S大鼠的动脉血压，降低RSNA。然而，RSNA对氯化钠的反应性在两组中都没有差异。(3)在0.3M氯化钠输注过程中，Dahl-S大鼠的摄水量较Dahl-R大鼠减少。2.接下来，我们利用清醒的SpragueDawley大鼠，检测了RSNA对中枢盐负荷的反应性。静脉注射高渗氯化钠溶液后的抑制反应：(1)在戊巴比妥钠麻醉下显著减弱；(2)在清醒大鼠不吸水时明显增强；(3)在去窦弓神经清醒大鼠中观察到；(4)用加压素V_1拮抗剂(OPC-21268，i.v)预处理后显著减弱。而不是V2拮抗剂(OCP-31260)。

项目成果

Tanaka, H., Ueta, Y., Yamashita, U., Kannan, H.and Yamashita, H.: "Biphasic changes in behavioral, endocrine, and sympathetic systems in adjuvant arthritis in Lewis rats." Brain Res.Bull.39. 33-37 (1996)

Tanaka, H.、Ueta, Y.、Yamashita, U.、Kannan, H. 和 Yamashita, H.：“Lewis 大鼠佐剂关节炎中行为、内分泌和交感系统的双相变化。”

Kannan, H., Tanaka, H., Kunitake, T., Ueta, Y., Hayashida, Y.and Yamashita, H.: "Activation of sympathetic outflow by recombinant human interleukin-1beta in conscious rats." Am.J.Physiol.270. R479-R485 (1996)

Kannan, H.、Tanaka, H.、Kunitake, T.、Ueta, Y.、Hayashida, Y. 和 Yamashita, H.：“重组人白细胞介素 1β 在清醒大鼠中激活交感神经流出。”

Kannan,H.: "Activation of sympathetic cutflow by recombinant human interleukin-1β in conscious rats." Am.J.Physiol.270. R479-R485 (1996)

Kannan, H.：“重组人白细胞介素 1β 在清醒大鼠中激活交感神经切流。”Am.J.Physiol.270（1996）。

Ueta,Y.: "Does recurrent inhibition exist in the paraventricular magnocellular neurosecretory cells in the male rat?" Jpn.J.Physiol.45. 913-919 (1995)

Ueta,Y.：“雄性大鼠的室旁大细胞神经分泌细胞是否存在反复抑制？”

Kannan,H.: "Changes in renal sympathetic nerve activities in the regulation of body fluid balance with special reference to central neuropeptides in conscious rats." Jpn.J.Physiol.46. 111-122 (1996)

Kannan，H.：“肾交感神经活动在体液平衡调节中的变化，特别是清醒大鼠中的中枢神经肽。”