Effects of corticosteroids on plasma angiotensinogen and renin activity.
Effects of corticosteroids on plasma angiotensinogen and renin activity.
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皮质类固醇对血浆血管紧张素原和肾素活性的影响。
DOI：
10.1152/ajplegacy.1969.217.5.1396
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发表时间：
1969
期刊：
影响因子：
--
通讯作者：
G. Masson
中科院分区：
文献类型：
--
作者：
A. Nasjletti;G. Masson
方法将体重135-170g的雌性Sprague-Dawley大鼠（查尔斯河品系）在乙醚麻醉下进行双侧肾上腺切除，并分成每组至少5只动物的组。实验动物从肾上腺切除术时开始，每天皮下注射一次醋酸脱氧皮质酮（DCA）、醋酸d-醛固酮、游离皮质酮或醋酸皮质醇。前两种类固醇是油溶液，后两种是盐悬浮液。一些醛固酮治疗组每天接受两次注射。皮质酮和皮质醇的剂量水平为0.25、1和5毫克/天； DCA 剂量水平在 0.05 至 5 mg 之间；醛固酮的剂量水平在 2 至 125 pg 之间。就钠潴留而言，2 pug 醛固酮的剂量大约相当于 0.05 mg DCA (34)。所有这些动物都喂食标准狐食并饮用自来水。对照动物包括饮用自来水的正常大鼠和饮用自来水和1%盐水的肾上腺切除大鼠。每天测量体重。第6天，用乙醚轻麻醉动物，从主动脉抽血，先加肝素测定血浆肾素活性和肾素底物，然后不加肝素测定血清钠和钾。通过在用含有250U/ml的肝素溶液清洗的注射器中收集约1.5ml血液来获得血浆肾素活性和血管紧张素原的样品。根据 Boucher 等人 (2) 的微量方法测定血浆肾素活性，并稍加修改：将 0.1 ml 血浆与过量的大鼠血管紧张素原一起孵育 16 小时而不是 12 小时。在经喷托啉处理的大鼠中对形成的血管紧张素进行测定，结果以每 0.1 毫升血浆每 16 小时孵育的血管紧张素 II 纳克 (ng) 表示。肾素底物是通过在存在过量大鼠肾素的情况下孵育血浆后血管紧张素的释放来估计的。每个培养箱含有 0.1 或 0.2 ml 血浆、1 ml 0.1 M、pH 6.5 磷酸盐缓冲液（含 0.02 M EDTA）、0.05 ml 含 1.25 Goldblatt 单位大鼠肾素的盐水、4 滴二异丙基氟磷酸盐和 0.9% 盐水，最终体积为 2 ml。 37℃孵育15分钟后，将管放入沸水中，然后离心。上清液用喷托啉处理过的进行测定
METHODSFemale Sprague-Dawley rats (Charles River strain) weighing 135-170 g were bilaterally adrenalectomized under ether anesthesia and divided into groups of at least five animals each. Experimental animals received, starting at the time of adrenalectomy, one daily subcutaneous injection of deoxycorticosterone acetate (DCA), d-aldosterone acetate, free corticosterone, or cortisol acetate. The first two steroids were in oil solution and the last two in saline suspension. Some aldosterone-treated groups received two daily injections. Corticosterone and cortisol were administered at the dose levels of 0.25, 1, and 5 mg/day; DCA at dose levels between 0.05 and 5 mg; and aldosterone at dose levels between 2 and 125 pg. The dose of 2 pug of aldosterone is approximately equipotent to 0.05 mg of DCA in terms of sodium retention(34). All these animals were fed a standard fox chow and given tap water to drink. Control animals consisted of normal rats on tap water and of adrenalectomized rats on tap water and on 1% saline. Body weight was measured daily. On the 6th day, animals were lightly anesthetized with ether and blood was drawn from the aorta, first with heparin for determination of plasma renin activity and renin substrate, and then without heparin for determination of serum sodium and potassium. Samples for plasma renin activity and angiotensinogen were obtained by collecting about 1.5 ml of blood in a syringe washed with a heparin solution containing 250 U/ml. Plasma renin activity was determined according to the micromethod of Boucher et al.(2) with a minor modification: 0.1 ml of plasma was incubated with an excess of rat angiotensinogen during 16 rather than 12 hr. The angiotensin formed was assayed in pentolinium-treated rats and results are expressed in nanograms(ng) of angiotensin II per 0.1 ml of plasma per 16 hr incubation. Renin substrate was estimated from the release of angiotensin after incubation of plasma in the presence of an excess of rat renin. Each incubate contained 0.1 or 0.2 ml of plasma, 1 ml of buffer phosphate 0.1 M, pH 6.5, containing 0.02 M EDTA, 0.05 ml of saline containing 1.25 Goldblatt units of rat renin, 4 drops of diisopropylfluorophosphate, and 0.9% saline to a final volume of 2 ml. After incubation during 15 min at 37 C, the tubes were placed in boiling water and then centrifuged. The supernatant was assayed in pentolinium-treated