The influence of low Na diet on the sympathetic nervous system and the alpha-receptor of renal basolateral membrane in spontaneously hypertensive rat.

低钠饮食对自发性高血压大鼠交感神经系统及肾基底外侧膜α受体的影响

• 批准号: 62570400
• 负责人: FUKIYAMA Koshiro
• 金额: $ 1.15万
• 依托单位: Faculty of medicine, University of the Ryukyus
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62570400/
• 关键词: Spontaneously hypertensive rat; Low sodium diet; Renal basolateral membrane; α受容体; 高血圧自然発症ラット(SHR); 腎尿細管側低膜

In Wistar rats bred successively on a diet containing the minimum sodium required for normal growth, blood pressure was lower and sympathetic nervous function was suppressed compared to those on normal sodium diet. However, SHR bred on the same sodium depleted diet grew up to hypertensive. To clarify why dietary sodium restriction has no effect to prevent hypertension in SHR, we studied an influence of sodium depletion on alpha-adrnergic receptors which were concerned with reabsorption of sodium in the renal tubules.Wistar Kyoto rat (WKY) and SHR were fed with a diet containing low Na (0.05%) or normal Na (0.4%). One day after the measurements of blood pressure, body weight and 24 hour urinary Na output at the age of 6, 8, 20 weeks, the kidneys were removed and the basolateral membranes of renal proximal tubules were preparated using Percall. Assay of adrenergic receptors was accomplished through the use of [^3H]-prazosin, alpha-1 antagonist, and [^3H]-rauwolscine, alpha-2 antagonist.B … More ody growth and blood pressure in WKY on low Na diet were similar to those on normal Na diet. Maximum binding (Bmax) for alpha-1 receptors was not different between the normal-and low-Na group at any age. Dissociation constants (Kd) increased at 8 weeks of age with no difference between the both groups. Bmax and Kd for alpha-2 receptor was similar between two groups in WKY.There was no difference in body growth and blood pressure between the low- and normal-Na group in SHR. Blood pressure increased to a hypertensive level at the age of 8 weeks. Urinary sodium excretion for 24 hours was less in SHR on low-Na than the expected. There was no significant difference in both Bmax and Kd for alpha-1 receptor between the normal-and low-Na group in SHR at any age. Bmax for the alpha-2 receptor increased markedly at 8 weeks of age in SHR on low-Na, while it increased slightly but significantly with aging in SHR on normal-Na diet. Bmax at 8 weeks of age on low-Na was higher than that in SHR on normal-Na diet or WKY on low-Na. Kd for alpha-2 receptor was similar between the 2 groups at all age of the week. The results suggest that SHR has access to increase alpha-2 receptors in the renal tubules even under sodium restriction, which might accelerate Na reabsorption and produce hypertension. Less

在连续饲养的Wistar大鼠饮食中含有正常生长所需的最低钠，血压较低，交感神经功能受到抑制相比，那些正常的钠饮食。然而，在相同的钠耗尽饮食下繁殖的SHR长大后会出现高血压。为阐明饮食限钠不能预防自发性高血压（SHR）高血压的原因，我们用低钠（0.05%）和正常钠（0.4%）饲料喂养Wistar京都大鼠（WKY）和SHR，研究了钠缺乏对肾小管α-肾上腺素能受体的影响。分别于6、8、20周龄测定血压、体重和24小时尿钠量，术后1 d取肾，用Percall法分离近端肾小管基底外侧膜。通过使用α-1拮抗剂[^3 H]-哌唑嗪和α-2拮抗剂[^3 H]-萝芙木碱完成肾上腺素能受体的测定。B ...更多信息 低钠组WKY的生长发育和血压与正常钠组相似。在任何年龄，正常和低钠组之间α-1受体的最大结合（Bmax）没有差异。解离常数（Kd）在8周龄时增加，两组之间没有差异。WKY组与正常组间α 2受体的Bmax和Kd值无显著性差异，SHR低钠组与正常组间的血压和体质量无显著性差异。8周龄时血压升高至高血压水平。低钠组SHR 24小时尿钠排泄量低于预期值。SHR各年龄组α 1受体的Bmax和Kd值在正常和低钠组之间均无显著性差异。低钠组SHR的α 2受体Bmax在8周龄时显著增加，而正常钠饮食组SHR的Bmax随着年龄的增长略有增加但显著。低钠组8周龄Bmax高于正常钠组SHR和低钠组WKY。α-2受体的Kd在两组之间在所有周龄都相似。结果提示，SHR在限钠条件下也能增加肾小管α 2受体，这可能会加速钠的重吸收，导致高血压。少

项目成果

K.Fukiyama,et al.: Hypertension. 9. 552 (1987)

K.Fukiyama 等：高血压。

K. Fukiyama et al.: "Sympathetic function in the offspring derived from breeders on low sodium diet or diuretic therapy in spontaneously hypertensive rats." Hypertention. 9. 552 (1987)

K. Fukiyama 等人：“对自发性高血压大鼠进行低钠饮食或利尿治疗的饲养者所产生的后代的交感功能。”

K.Fukiyama,et al.: Jap.Circ.J. 50. 1170-1173 (1986)

K.Fukiyama 等人：Jap.Circ.J.

K. Fukiyama et al.: "Blood pressure and sympathetic nervous function in spontaneously hypertensive rats derived from breeders on low sodium diet." Jap. Circ. J. 50. 1170-1173 (1986)

K. Fukiyama 等人：“低钠饮食饲养的自发性高血压大鼠的血压和交感神经功能。”

K. Fukiyama et al: Jap Ciro J. 50. 1170-1173 (1986)

K. Fukiyama 等人：Jap Ciro J. 50. 1170-1173 (1986)