Stern N, Beck F J, Eggena P, Phillips D, Sowers J R
Clin Exp Hypertens A. 1983;5(9):1543-57. doi: 10.3109/10641968309069510.
This study examines the role of gluco- and mineralcorticoids in the regulation of the renin-angiotensin system and blood pressure in the spontaneously hypertensive rat (SHR). Effects of adrenalectomy and selective treatment with either aldosterone (30 micrograms/kg/day) or dexamethasone (60 micrograms/kg/day) on plasma renin substrate, active renin (PRA), total renin and blood pressure were studied in 10 week old SHR and control WKY rats. Systolic blood pressure was moderately lower in adrenalectomized rats (129 +/- 2 mm Hg vs 137 +/- 4 mm Hg in control WKY and 145 +/- 4 mm Hg vs 160 +/- 3 mm Hg in control SHR) but could be restored to the control range by aldosterone. Dexamethasone repletion induced substantial increments of systolic blood pressure to comparable levels in both species (202 +/- 8 mm Hg in WKY and 192 +/- 6 mm Hg in SHR). Renin substrate was markedly lower in adrenalectomized, saline repleted rats. This could be reversed by dexamethasone in both species and by aldosterone in WKY rats only. Both PRA and total renin were higher (p less than 0.01) in the adrenalectomized, saline repleted state. This increase was not observed in aldosterone repleted rats. However, dexamethasone inhibited the adrenalectomy associated increase of PRA and total renin in SHR but not in WKY rats. Differences in blood pressure between SHR and WKY persist even in adrenalectomized state despite comparable stimulation of the renin system. Conversely, while blood pressure of both species responds similarly to selective corticosteroids therapy, the response of the renin-angiotensin system in SHR and WKY rats is distinct. Therefore factors other than the adrenal gland and the renin system must be involved in the determination of the high blood pressure in SHR.
本研究探讨了糖皮质激素和盐皮质激素在自发性高血压大鼠（SHR）肾素 - 血管紧张素系统调节及血压调控中的作用。对10周龄的SHR和对照WKY大鼠，研究了肾上腺切除术以及分别用醛固酮（30微克/千克/天）或地塞米松（60微克/千克/天）进行选择性治疗对血浆肾素底物、活性肾素（PRA）、总肾素和血压的影响。肾上腺切除术后大鼠的收缩压适度降低（对照WKY大鼠为129±2毫米汞柱，对照SHR大鼠为145±4毫米汞柱，而对照WKY大鼠为137±4毫米汞柱，对照SHR大鼠为160±3毫米汞柱），但醛固酮可使其恢复至对照范围。补充地塞米松可使两种大鼠的收缩压大幅升高至相当水平（WKY大鼠为202±8毫米汞柱，SHR大鼠为192±6毫米汞柱）。肾上腺切除并用生理盐水补充的大鼠肾素底物明显降低。在两种大鼠中，地塞米松均可使其逆转，而在WKY大鼠中，醛固酮也可使其逆转。肾上腺切除并用生理盐水补充状态下，PRA和总肾素均较高（p＜0.01）。在补充醛固酮的大鼠中未观察到这种升高。然而，地塞米松抑制了SHR中与肾上腺切除相关的PRA和总肾素升高，但对WKY大鼠无此作用。尽管肾素系统受到类似刺激，但在肾上腺切除状态下，SHR和WKY大鼠之间的血压差异仍然存在。相反，虽然两种大鼠的血压对选择性皮质类固醇治疗的反应相似，但SHR和WKY大鼠肾素 - 血管紧张素系统的反应却不同。因此，除肾上腺和肾素系统外，其他因素也必定参与了SHR高血压的形成。
