RU486对正常人和库欣综合征患者垂体—肾上腺轴的影响及…

本文观察了１０例正常人和１４例库欣综合征患者垂体－肾上腺轴在单次口服ＲＵ４８６ ４ｍｇ／ｋｇ后的反应。正常人在８ｐｍ口服ＲＵ４８６后连续２天８Ａｍ的血促肾上腺皮质激素（ＡＣＴＨ）和皮质醇（Ｆ）均明显升高（Ｐ〈０．０１，Ｐ〈０．００１），服药后第一天２４ｈ尿Ｆ亦明显升高（Ｐ〈０．００１）。库欣综合征组服药后连续观察２天上述激素水平无明显改变。正常组服药后连续２天的血Ｆ，ＡＣＴＨ及２４ｈ尿Ｆ较服药前所     

HLA-DR-DQ连锁基因单倍体与成人缓慢进展型和速发型1型糖尿病的相关性研究

目的探讨ＨＬＡＤＲＤＱ连锁基因单倍体与成人缓慢进展型１型糖尿病（ＳＰＩＤＤＭ）和速发型１型糖尿病（ＦＰＩＤＤＭ）的相关性。方法利用ＰＣＲ／ＳＳＰ技术检测了５２例ＳＰＩＤＤＭ患者、３０例ＦＰＩＤＤＭ患者和１３０例正常人的ＨＬＡＤＲＤＱ连锁基因频率。结果①ＨＬＡＤＱＡ１０３０１ＤＱＢ１０２０１和ＤＱＡ１０５０１ＤＱＢ１０２０１连锁基因单倍体与ＳＰＩＤＤＭ（Ｐｃ＜０．００１）和ＦＰＩＤＤＭ（Ｐｃ＜０．００１）均呈显著正相关；②ＨＬＡＤＱＡ１０３０１ＤＱＢ１０３０１和ＤＱＡ１０３０１ＤＱＢ１０６０２连锁基因单倍体与ＳＰＩＤＤＭ呈显著正相关（Ｐｃ＜０．００１）；③ＨＬＡＤＱＡ１０３０１ＤＱＢ１０３０２，ＤＱＡ１０３０１ＤＱＢ１０３０３及ＤＲＢ１０３０１ＤＱＡ１０３０１ＤＱＢ１０２０１连锁基因单倍体与ＦＰＩＤＤＭ呈显著正相关（前二者Ｐｃ＜０．０１，后者Ｐｃ＜０．００１）。结论ＳＰＩＤＤＭ和ＦＰＩＤＤＭ虽然均为自身免疫性糖尿病，但其ＨＬＡ表型并不完全相同，不同的ＨＬＡ表型可能是决定患者起病方式及病情发展不同的因素之一。     

健康老年人和老年心衰,糖尿病患者心率变异性的初步分析

应用动态心电图仪，定量观察了６０例健康人（其中青年及老年人各３０例）、３０例老年心衰患者、３０例老年糖尿病患者的心率变异性。结果显示：健康老年人２４小时正常Ｒ－Ｒ间期标准差（ＳＴＳＤ）为１２３．５±１８．８ｍｓ，２４小时内连续５分钟节段正常Ｒ－Ｒ间期标准差的平均数（ＳＤ）为４５．４±１１．３ｍｓ，２４小时内连续５分钟节段平均正常Ｒ－Ｒ间期标准差（ＳＤＡＮＮ）为１１２．３±１８．３ｍｓ，２４小时内每２个相邻Ｒ－Ｒ间期大于５０ｍｓ的绝对数（ＲＲ_（５０））为５６６６．６±６２４９．２，低频频域测量（ＬＦＰＳＤ）５４４．２±２８６．４ｍｓ￣２／Ｈｚ，高频频域测量（ＨＦＰＳＤ）９０．７±１２１．２ｍｓ￣２／Ｈｚ，均明显低于青年人（Ｐ＜０．００１）。老年心衰患者的ＨＲＶ明显低于健康人，两组间的ＳＴＳＤ、ＳＤ、ＳＤＡＮＮ、ＬＦＰＳＤ比较，差异有显著性（Ｐ＜０．００１）；糖尿病患者ＳＴＳＤ、ＳＤ，ＳＤＡＮＮ，ＬＦＰＳＤ均明显低于健康人（Ｐ＜０．０１）。提示心率变异性可作为判断老年人糖尿病、心衰等预后的手段之一。     

干扰素对人甲状腺细胞表面抗原表达的影响

目的研究干扰素（ＩＦＮα、ＩＦＮγ）及激素对人正常甲状腺细胞表面抗原表达的影响,以探讨ＩＦＮα导致自身免疫性甲状腺病（ＡＩＴＤ）的可能机制。方法应用ＩＦＮα、ＩＦＮγ、促甲状腺激素（ＴＳＨ）及催乳素（ＰＲＬ）,刺激体外培养的来自６名正常人的甲状腺细胞,通过免疫荧光染色及流式细胞仪测定其表面抗原—ＨＬＡＤＲ、细胞间粘附分子１（ＩＣＡＭ１）、Ｂ７．１和甲状腺过氧化物酶（ＴＰＯ）的表达。结果（１）ＩＦＮα明显诱导甲状腺细胞表达ＩＣＡＭ１、Ｂ７．１和ＴＰＯ（分别为Ｐ＜０．０１、Ｐ＜０．０１、Ｐ＜０．０５）;（２）ＩＦＮγ明显诱导甲状腺细胞表达ＨＬＡＤＲ、ＩＣＡＭ１,但对Ｂ７．１的表达无促进作用（Ｐ＜０．０１、Ｐ＜０．０１、Ｐ＞０．０５）;（３）ＰＲＬ显著诱导甲状腺细胞表达ＩＣＡＭ１、Ｂ７．１和ＴＰＯ（Ｐ＜０．０５、Ｐ＜０．０１、Ｐ＜０．０１）。结论协同刺激信号对ＡＩＴＤ的发生起着关键作用。ＩＦＮα显著诱导甲状腺细胞表达协同刺激信号（Ｂ７．１）和自身抗原ＴＰＯ,可能是临床应用ＩＦＮα诱致ＡＩＴＤ的致病原因之一。ＰＲＬ在产后甲状腺炎发病和发展中的作用应予以关注     

Western印迹方法测定血清中胰岛素样生长因子结合蛋白-3水平

目的　研究正常人及生长激素分泌异常病人血清中胰岛素样生长因子结合蛋白３（ Ｉ Ｇ Ｆ Ｂ Ｐ３） 的水平。方法　本文采用 Ｗｅｓｔｅｒｎ 印迹方法测定２０ 例正常人,３３ 例活动性肢端肥大症病人和３４ 例特发性生长激素缺乏症（ Ｉ Ｇ Ｈ Ｄ） 病人血清 Ｉ Ｇ Ｆ Ｂ Ｐ３ 水平。结果　正常成人血清中存在五种分子量不同的 Ｉ Ｇ Ｆ Ｂ Ｐ, Ｉ Ｇ Ｆ Ｂ Ｐ３ 含量为最高。本文测定了２０ 例正常成人和６７ 例生长激素分泌异常患者血清 Ｉ Ｇ Ｆ Ｂ Ｐ３ 的相对光密度（ Ｒ Ｏ Ｄ） ,正常人血清 Ｉ Ｇ Ｆ Ｂ Ｐ３ 含量为（１ ．１ ±０ ．４） Ｒ Ｏ Ｄ,活动性肢端肥大病人为（２ ．７ ±１ ．２） Ｒ Ｏ Ｄ,明显高于正常成人（ Ｐ＜ ０ ．０１） , Ｉ Ｇ Ｈ Ｄ 病人为（０ ．４ ±０ ．２） Ｒ Ｏ Ｄ,明显低于正常成人（ Ｐ＜ ０ ．０１） 。血清生长激素与 Ｉ Ｇ Ｆ Ｂ Ｐ３ 、胰岛素样生长因子 Ｉ与 Ｉ Ｇ Ｆ Ｂ Ｐ３ 均呈正相关（ Ｐ＜０ ．０５） 。结论　 Ｗｅｓｔｅｒｎ 印迹测定血清 Ｉ Ｇ Ｆ Ｂ Ｐ３ 正常值和病理值提示 Ｉ Ｇ Ｆ Ｂ Ｐ３ 浓度的变化与生长激素功能状态密切相关,并依赖 Ｇ Ｈ。     

类风湿关节炎病人血清细胞因子水平以及与炎症指标的相关性

目的：进一步研究细胞因子在类风湿关节炎（ＲＡ）中的作用以及与疾病的关系。方法：随机就诊的７２名门诊及住院ＲＡ病人红细胞沉降率（ＥＳＲ）、Ｃ反应蛋白（ＣＲＰ）以及细胞因子白细胞介素１α（ＩＬ１α）、ＩＬ１β、ＩＬ２、ＩＬ６、肿瘤坏死因子α（ＴＮＦα）、粒细胞单核细胞集落刺激因子（ＧＭＣＳＦ）被测定。全部数据用于ＲＡ病人细胞因子水平的研究，并对细胞因子与炎症指标的相关性进行探讨。结果：ＲＡ病人血清ＧＭＣＳＦ、ＴＮＦα水平较健康对照组明显增高（Ｐ＜０００１）。ＩＬ６、ＧＭＣＳＦ与炎性指标ＥＳＲ（ｒ＝０２６，Ｐ＜００１；ｒ＝０２８，Ｐ＜００２）和ＣＲＰ（ｒ＝０４０，Ｐ＜００００１；ｒ＝０４７，Ｐ＜００００１）呈正相关。结论：ＲＡ病人血清ＩＬ６、ＧＭＣＳＦ、ＴＮＦα较其他细胞因子与ＲＡ疾病有更密切的相关性。细胞因子作为重要的免疫物质参与炎症反应在ＲＡ的病理过程中起到了重要作用。     

急性非淋巴细胞白血病P-糖蛋白表达及排出活性检测的临床意义

目的探讨成人初治急性非淋巴细胞白血病（ＡＮＬＬ）Ｐ糖蛋白（Ｐｇｐ）表达及罗丹明１２３排出活性（Ｒ１２３Ｅ）与预后的关系。方法流式细胞术检测ＡＮＬＬ白血病细胞Ｒ１２３Ｅ及Ｐｇｐ表达。结果Ｒ１２３Ｅ＋率及Ｐｇｐ＋率分别为３９５％及３４２％。Ｍ３的Ｒ１２３Ｅ＋率（０／６）明显低于其他亚型（４３８％）（Ｐ＜００５）。Ｐｇｐ表达与活性存在明显相关性（Ｐ＜０００１），７８９％的患者表达与活性一致（１０例Ｐｇｐ＋Ｅ＋，２０例Ｐｇｐ－Ｅ－）；２１１％存在表达与活性分离（３例Ｐｇｐ＋Ｅ－，５例Ｐｇｐ－Ｅ＋），Ｐｇｐ－Ｅ＋提示非Ｐｇｐ介导的排出活性在ＡＮＬＬ耐药中可能具有重要作用。Ｒ１２３Ｅ＋完全缓解（ＣＲ）率（２／１１，１８２％）及Ｐｇｐ＋者的ＣＲ率（２／１０，２０％），明显低于Ｒ１２３Ｅ－的９２９％（１３／１４）及Ｐｇｐ－的８６７％（１３／１５）（Ｐ分别＜００１及＜０００１）。结论Ｐｇｐ表达及活性检测在成人ＡＮＬＬ中均具有重要的预后意义     

消化性溃疡和胃癌病人血清可溶性IL－2受体和纤维结合素的观察

用多克隆单克隆夹心ＥＬＩＳＡ法和单向扩散法测定溃疡病和胃癌患者血清可溶性白细胞介素２受体（ｓｏｌｕｂｌｅＩＬ－２ｒｅｃｅｐｔｏｒｓ，ＳＩＬ－２Ｒ）和纤维结合素（ｆｉｂｒｏｎｅｃｔｉｎ，ＦＮ）。结果显示溃疡病血清ＳＩＬ－２Ｒ和ＦＮ分别为２１２．９２±１２２．２７Ｕ／ｍｌ和２９８．０９±３３．４６ｎｇ／ｍｌ，胃癌分别为５５９．２７±２３４．０１Ｕ／ｍｌ和３３６．６５±３９．２１ｎｇ／ｍｌ。与正常人２４０．０±９７．０７Ｕ／ｍｌ和３２３．６４±２８．２１ｎｇ／ｍｌ比较，胃癌患者ＳＩＬ－２Ｒ水平明显升高（Ｐ＜０．００１），其中肿瘤有转移者低于无转移者（Ｐ＜０．０５）。这表明血清ＳＩＬ－２Ｒ和ＦＮ检测可做为胃癌病人病情监测和判断预后的指标，亦可用以签别良性和恶性溃疡。     

红细胞膜脂流动性与急性心肌梗塞病情程度的相关研究

本研究应用荧光分光光度计偏振技术对１６例急性心肌梗塞（ＡＭＩ）患者外周血红细胞膜脂流动性（ＬＦＵ）进行了测定。结果表明，ＡＭＩ患者外周血红细胞ＬＦＵ明显低于正常人（Ｐ＜０．００１），且在ＡＭＩ后有一先降低后逐渐恢复的动态过程，其中ＡＭＩ后第１天和第３天以及发生严重并发症的患者降低更为显著（分别ｐ＜０．００１和Ｐ＜０．０５），表明红细胞ＬＦＵ的变化水平在很大程度上反映了ＡＭＩ时心肌缺血程度和病情的严重性。     

LMP2与LMP7基因多态性与强直性脊柱炎并发虹睫炎易感性关系的研究

目的研究ＬＭＰ基因多态性与强直性脊柱炎并发虹睫炎发病的关系。方法应用ＰＣＲ对正常人和病人进行ＨＬＡＢ２７检测以及ＬＭＰ２和ＬＭＰ７扩增。ＣｆｏＩ进行限制性酶切图谱分析。结果强直性脊柱炎有虹睫炎（ＡＳ＋ＡＡＵ）病史以及单纯虹睫炎（ＡＡＵ）患者ＬＭＰ２基因ＢＢ纯合型较正常人以及强直性脊柱炎（ＡＳ）患者明显增高（Ｐ＜００５）,ＡＳ＋ＡＡＵ患者ＢＢ型ＯＲ＝３６,ＡＡＵ患者ＢＢ型ＯＲ＝５８３。ＬＭＰ７基因多态性无明显差别。结论在我国汉人中,ＬＭＰ２基因多态性与ＡＳ＋ＡＡＵ以及ＡＡＵ发病存在明显相关关系。     

The antiglucocorticoid and antiprogestin steroid RU 486 suppresses the adrenocorticotropin response to ovine corticotropin releasing hormone in man

The glucocorticoid and progesterone antagonist RU 486 normalizes the clinical and biochemical features of hypercortisolism in patients with nonpituitary Cushing's syndrome, presumably by antagonizing the action(s) of cortisol. Since RU 486 has progesterone agonist activity in addition to its progesterone antagonist action, the possibility that it might have some glucocorticoid agonist action did not seem unreasonable. To test this hypothesis we examined the effects of RU 486 on pituitary ACTH secretion in 10 patients with primary adrenal insufficiency in whom glucocorticoid replacement was withheld for 36 h. Each patient received, in randomized sequence 3-7 days apart, an oral dose of placebo, RU 486 (20 mg/kg), cortisol (0.1 mg/kg), or a combination of RU 486 and cortisol at 1800 h. Two hours later, an iv bolus dose of ovine CRH (1 microgram/kg) was administered, and plasma ACTH levels were measured serially for 3 h. RU 486 suppressed ovine CRH-stimulated ACTH secretion, albeit less than cortisol. Its glucocorticoid agonist effect was calculated to be approximately 1/250th that of cortisol on a weight basis. Additionally, RU 486 partially antagonized cortisol-induced suppression of ACTH secretion. These findings suggest that RU 486 is a partial glucocorticoid agonist and offer some insight as to its action in patients with Cushing's syndrome. Whether this degree of glucocorticoid agonist activity is adequate to support life, however, is not known.     

Pituitary-adrenal response to the antiglucocorticoid action of RU 486 in Cushing's syndrome

RU 486 [17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)17 alpha-(prop-1-ynyl)estra-4,9-dien-3-one] is a steroid analog which antagonizes glucocorticoid action at the receptor level. The pituitary-adrenal response to RU 486 was evaluated in patients with Cushing's syndrome. The acute administration of 400 mg RU 486 at 0800 h in five patients with Cushing's disease induced no significant change in plasma cortisol during the next 10 h compared with the administration of placebo. However, prolonged administration (400 mg daily for 3 days) caused activation of the pituitary-adrenal axis; urinary cortisol increased the most from 727 to 5720, 830 to 8200, 610 to 1020, 110 to 570, and 300 to 990 micrograms/day. Plasma cortisol and lipotropins increased to a lesser extent. Hormone changes appeared on the second day of drug administration and lasted up to 3-4 days after the drug was discontinued. In two patients with nonpituitary-dependent Cushing's syndrome, RU 486 induced no significant change in steroid secretion. We conclude that RU 486 induced a delayed and prolonged pituitary-adrenal response in Cushing's disease; whether the resulting cortisol overproduction will overcome the peripheral effect of RU 486 remains to be determined.     

Plasma ACTH and cortisol responses to TRF, vasopressin or hypoglycemia in cushing's disease and nelson's syndrome.

The response of plasma ACTH and/or cortisol concentrations to thyrotropin-releasing-factor (TRF), vasopressin, and insulin administration was determined in 5 patients with Nelson's syndrome and 12 patients with untreated Cushing's disease. TRF administration was associated with a mean increment of 267 pg/ml in plasma ACTH concentrations in patients with Nelson's syndrome, and of 42 pg/ml in patients with Cushing's disease. The increment in plasma cortisol concentrations in the latter group was 12 mug%. No ACTH or cortisol response was observed in normal subjects. Patients with Cushing's disease or Nelson's syndrome exhibited significantly greater increments in plasma ACTH concentrations in response to vasopressin administration (P less than .05, P less than .02 respectively) than did normal subjects; the increment in cortisol concentration was also greater, (P less than .05), in patients with Cushing's disease than in normal subjects. No significant difference was present between patients with Cushing's disease and Nelson's syndrome with regard to the magnitude of the ACTH response to vasopressin administration. In contrast, the increment in plasma cortisol and plasma ACTH concentrations following insulin induced hypoglycemia was significantly less in patients with Cushing's disease than seen in normal subjects, (P less than .001, P less than .05 respectively); while this stimulus was associated with a significantly greater increment in plasma ACTH concentrations in patients with Nelson's syndrome as compared to that seen in normal subjects, (P less than .01) and in patients with Cushing's disease (P less than .01). These findings indicate that pituitary function in patients with Nelson's syndrome is not autonomous and suggest the possibility that altered central nervous regulatory mechanism might play a role in the etiology of the pituitary tumors which are frequently associated with this syndrome. The TRF induced rise in plasm cortisol and ACTH concentrations in patients with Cushing's disease and Nelson's syndrome suggests the possibility of altered hypothalamic or pituitary receptors in such patients.     

The antiglucocorticoid and antiprogestin steroid RU 486: its glucocorticoid agonist effect is inadequate to prevent adrenal insufficiency in primates

The glucocorticoid receptor antagonist RU 486 has been used to treat the hypercortisolism of patients with nonpituitary Cushing's syndrome. Since endogenous cortisol production fluctuates in many patients with either the ectopic ACTH syndrome or adrenocortical tumors, treatment of these patients with a fixed dose of RU 486 introduces the risk of adrenal insufficiency. While RU 486 possesses some glucocorticoid agonist activity in addition to its potent antagonist effects, it is not known whether this intrinsic agonist activity is of sufficient magnitude to prevent adrenal insufficiency and sustain life. To answer this question three groups of bilaterally adrenalectomized cynomolgus monkeys (n = 5/group) were randomized to receive a daily injection of RU 486 (5 mg/kg.day), cortisol (1.25 mg/kg.day), or saline (placebo). All adrenalectomized monkeys received weekly im injections of deoxycorticosterone pivalate (1 mg) to prevent mineralocorticoid deficiency. Five sham-adrenalectomized monkeys served as controls and received im injections of saline (placebo). Blood was collected before adrenalectomy or sham operation and every 3 days postoperatively for measurement of serum electrolytes, blood urea nitrogen, and creatinine; plasma ACTH concentrations; and complete blood and differential cell counts. All sham-operated and cortisol-replaced adrenalectomized monkeys survived, and none developed overt biochemical evidence of adrenal insufficiency. All placebo and RU 486-replaced adrenalectomized monkeys expired within 33 days after adrenalectomy, presumably from adrenal insufficiency. These findings suggest that while RU 486 is a partial glucocorticoid agonist, its degree of glucocorticoid agonism is inadequate to prevent adrenal insufficiency and support life in adrenalectomized primates.     

ACTH secretion and adrenocortical responsiveness in Cushing's syndrome due to adrenocortical hyperplasia (author's transl)]

A radioimmunoassay for plasma ACTH has been developed utilizing highly purified human ACTH (Li) labelled with 125I by the lactoperoxidase method as a tracer and an ACTH antibody produced by immunization of rabbits with ACTH-Z (Organon). The assay is highly specific, reproducible and sensitive to 20 pg of ACTH per ml. Utilizing this technique, endogenous ACTH secretion, adrenal responsiveness to endogenous ACTH and hypothalamic pituitary adrenal feedback mechanisms have been assessed in normal subjects and in patients with Cushing's syndrome due to adrenocortical hyperplasia and nodular cortical hyperplasia. The potential effect of a negative feedback mechanism on the circadian rhythmicity after SU-4885 administration was assessed by initiating SU-4885 either at 9 p.m. or 8 a.m. In normal subjects, the circadian rhythm of ACTH was persistent and independent of a decrease in cortisol. However, in a single case of Cushing's syndrome due to adrenocortical hyperplasia, the circadian rhythm was different from that of normal subjects, possibly influenced by a negative feedback mechanism when SU-4885 was initiated at 8 a.m. In Cushing's syndrome due to adrenocortical and nodular cortical hyperplasia, a significant correlation was observed between the mean plasma ACTH and urinary 17-OHCS values before and after SU-4885 administration (r=0.743, p less than0.01). A significant correlation was also obtained in normal subjects between plasma ACTH and urinary 17-OHCS values (r=0.889, p less than 0.01). However, there was quantitatively more 17-OHCS excreted in the urine for a given plasma ACTH level in patients with Cushing's syndrome than in normal subjects. To assess the relative biological activity of endogenous and exogenously administered ACTH, the ratio of daily 17-OHCS during SU-4885 administration and Cortrosyn-Z administration was expressed as the Cortrosyn Equivalent Quotient (C.E.Q.). The correlation between plasma ACTH and C.E.Q. was similar and significant for normal subjects and patients with Cushing's syndrome (r=0.670, p less than 0.01). These data suggest that there is hyper-responsiveness of the adrenal glands to endogenous ACTH in Cushing's syndrome due to adrenocortical hyperplasia and nodular cortical hyperplasia and that the adrenal hyperactivity is not engendered by a qualitative change in the ACTH release from the pituitary gland. To assess pituitary suppressibility, dexamethasone was administered 40 days or more later following total adrenalectomy in 9 patients with Cushing's syndrome, 6 with adrenocortical hyperplasia and 3 with nodular cortical hyperplasia. One day after discontinuation of substitution therapy, 2 mg of dexamethasone was administered orally followed on successive days by 4 and 8 mg doses. In each instance, dexamethasone was given at midnight and the plasma ACTH concentration was determined at 9:00 a.m. on the day before and after administration of the dexamethasone. A patient with Addison's disease was studied as a control...     

The corticotropin-releasing hormone test in the postoperative evaluation of patients with cushing's syndrome

After surgical cure of Cushing's syndrome most patients develop transient secondary adrenal insufficiency that lasts for approximately 1 yr. Since ACTH-secreting pituitary adenomas generally respond to ovine CRH (oCRH), we tested the hypothesis that an early postoperative response to oCRH may indicate the presence of residual pituitary tumor and, therefore, predict recurrence. We also assessed the usefulness of oCRH for monitoring the recovery of the hypothalamic-pituitary-adrenal axis and for clarifying the pathophysiology of this condition. Thirty-four patients cured of Cushing's syndrome (29 with Cushing's disease, 3 with adrenal adenomas, and 2 with the ectopic ACTH syndrome) had an evening oCRH test 1-2 weeks after surgery. Nine patients (6 with Cushing's disease, 2 with adrenal adenomas, and 1 with the ectopic ACTH syndrome) participated in a longitudinal evaluation and had repeated oCRH and 1-h ACTH tests at 2-month intervals for a year after surgery. Patients were considered to be cured on the basis of at least 3 subnormal urinary [less than 20 micrograms/24 h (less than 55 nmol/day)] or morning plasma cortisol levels [0600-0900 h; less than 6 micrograms/dL (less than 170 nmol/L)] in the first 2 weeks after surgery. The plasma ACTH and cortisol responses to oCRH in the early postoperative period were subnormal in 23 and normal in 6 patients with Cushing's disease. Three patients developed recurrent Cushing's disease (3, 3, and 23 months after transphenoidal surgery). All 3 were among the 6 who had a normal early postoperative response to oCRH. All of the 23 patients who had a subnormal response to oCRH in the early postoperative period have remained in remission for an average follow-up period of 14 months (6-42 months). Thus, the recurrence rate was significantly greater in patients with normal oCRH tests in the early postoperative period (P less than 0.001, by chi 2 analysis). Surgically cured patients with adrenal adenomas or ectopic ACTH secretion also had subnormal plasma ACTH and cortisol responses to oCRH during the early postoperative period. During longitudinal evaluation for 12 months after surgery, the ACTH and cortisol responses to oCRH increased progressively (regardless of the cause of Cushing's syndrome). Cortisol responses to oCRH correlated significantly with the cortisol responses to exogenous ACTH (r = 0.89; P less than 0.00001). We conclude that most patients with Cushing's syndrome have suppressed responses to oCRH during the early postoperative period.(ABSTRACT TRUNCATED AT 400 WORDS)     

Circulating adrenomedullin is increased in patients with corticotropin-dependent Cushing's syndrome due to pituitary adenoma

It has been demonstrated that adrenomedullin, a newly discovered peptide with structural similarity to calcitonin gene-related peptide (CGRP), is expressed in pituitary gland and affects basal and corticotropin (ACTH)-releasing factor (CRF)-stimulated ACTH release in animals, thus suggesting its potential role in regulating the hypothalamus-pituitary-adrenal axis. To evaluate whether ACTH and cortisol levels affect adrenomedullin production in humans, we studied 14 patients with Cushing's syndrome due to pituitary adenoma and 8 patients with Cushing's syndrome due to adrenal tumor, with measurement of circulating adrenomedullin by a specific radioimmunoassay (RIA). Adrenomedullin concentrations were significantly higher in patients with pituitary adenoma (37.6 +/- 17.8 pg/mL) versus controls (13.7 +/- 6.1 pg/mL) and patients with adrenal adenoma (17.8 +/- 2.2 pg/mL). After pituitary surgical treatment, plasma adrenomedullin decreased significantly. In one patient with Cushing's syndrome due to pituitary adenoma who underwent simultaneous sampling of the inferior petrosal venous sinuses, the adrenomedullin concentration was significantly higher in plasma collected from the side with the adenoma and increased after CRF administration (delta increase, 42.6%), according to ACTH levels. Our findings indicate that circulating adrenomedullin is increased in Cushing's disease, and the pituitary gland may represent the site of the elevated production of adrenomedullin in this condition.     

Corticotropin releasing hormone stimulation test: diagnostic aspects in Cushing's syndrome

The effect of exogenous ovine Corticotropin-Releasing Hormone (oCRH) on plasma ACTH and cortisol levels was investigated in 10 normal volunteers and in 37 patients with Cushing's syndrome (26 with pituitary-dependent disease, 5 with an adrenal adenoma, 2 with an adrenal carcinoma and 4 with bilateral nodular hyperplasia). In all normal subjects and in patients with Cushing's disease, oCRH 100 micrograms as a bolus produced an increase in both plasma ACTH and cortisol. The peak of ACTH occurred after 15-30 min, while plasma cortisol showed highest levels between 30 and 60 min after oCRH administration. The hormonal response in Cushing's disease showed great variability with a clear hyperresponsiveness at least in 6 out of 26 patients with Cushing's disease. A slight and delayed response occurred in 3 cases of bilateral nodular adrenal hyperplasia, while a fourth case showed hyperresponsiveness similar to that found in pituitary-dependent Cushing's disease. No response was observed in patients with an adrenal tumor. Eleven patients with Cushing's disease were tested before and 1 month after pituitary microadenomectomy. After surgery basal cortisol levels were reduced in 10 and became unresponsive or less responsive to oCRH. ACTH patterns were variable with a normal response only in few cases. Although this test seems of limited value in the diagnosis of hypercortisolism, it is a useful tool to differentiate some types of Cushing's syndrome (adrenal tumor from pituitary-dependent Cushing's disease). Variable patterns of response in cases with bilateral nodular adrenal hyperplasia limit the usefulness of this test in recognizing this rare form of hypercortisolism.     

Effects of the antiglucocorticoid RU 486 on adrenal function in dogs

We studied the antiglucocorticoid effects of RU 486 given orally in doses of 5 (low), 20 (intermediate), and 50 mg/kg (high) daily for 10 days to seven female mongrel dogs. No changes in plasma ACTH or cortisol levels were produced by the 5 mg/kg dose. Plasma ACTH levels increased 3-fold with both intermediate and high dosages. Plasma cortisol levels rose 4-fold (P less than 0.05) within 2 days of commencing the high dose schedule and within 3 days with the intermediate dosage. Plasma aldosterone concentrations increased significantly only with the highest dose schedule. Plasma RU 486 levels rose progressively during the 10 days of RU 486 administration and with the highest dose remained elevated for 7 days after it was stopped. Plasma RU 486 levels measured by RIA and high pressure liquid chromatography were comparable. The monodemethylated metabolite of RU 486 changed in parallel to the parent compound. During the high dose of RU 486, there was a 4% increase in body weight, with a reduction in hematocrit and plasma protein concentration. Plasma electrolyte levels and osmolality did not change. We conclude that in dogs a daily RU 486 dose of 5 mg/kg does not alter adrenal function, whereas higher doses (20 and 50 mg/kg) induce increases in plasma ACTH and cortisol concentrations. Despite the blockade of glucocorticoid receptors by RU 486, the presence of isotonic hypervolemia suggests that there was no functional deficiency of cortisol at the renal tubule or it was overshadowed by augmented mineralocorticoid production and action.     

The effect of pulsatile human corticotropin-releasing hormone administration on the adrenal insufficiency that follows cure of Cushing's disease

Successful transsphenoidal surgery for Cushing's disease leads to secondary adrenal insufficiency in most patients. This form of transient adrenal insufficiency is thought to result from hypothalamic and pituitary suppression due to the preceding hypercortisolism. Whether the rate-limiting step in the recovery of adrenal function in this setting is the hypothalamic CRH neuron or the pituitary corticotroph cell, however, is not known. We studied this question by examining the response to ovine CRH (oCRH) before, during, and after prolonged pulsatile administration of human CRH (hCRH) beginning 1-2 weeks after curative microadenomectomy for Cushing's disease. Five patients cured of Cushing's disease received eight hCRH injections (1 microgram/kg) daily for 7 days. This CRH regimen was found previously to normalize plasma ACTH and cortisol patterns in patients with secondary adrenal insufficiency who had normal ACTH responses to a single injection of oCRH (hypothalamic adrenal insufficiency). The plasma ACTH and cortisol responses to oCRH (1 microgram/kg at 2000 h) were assessed immediately before, 2.5 h after, and 7 days after the end of pulsatile hCRH administration. To control for time-related improvement in the hormonal response to ovine CRH, an additional five patients cured of Cushing's disease underwent oCRH tests 1-2 and 3-4 weeks after transsphenoidal surgery, but did not receive hCRH. There was no significant difference in basal or oCRH-stimulated plasma ACTH and cortisol levels among any of the three oCRH tests in the patients who received hCRH. The baseline and oCRH-stimulated plasma ACTH and cortisol levels 1-2 and 3-4 weeks after surgery in the patients who did not receive pulsatile hCRH were similar to the values at those times in the patients who received pulsatile hCRH. Compared to normal subjects, however, both the hCRH-treated and non-hCRH-treated patients had significantly decreased peak and time-integrated plasma ACTH and cortisol responses to oCRH. We conclude that an impaired pituitary response to CRH contributes to the postoperative hypocortisolism of patients recently cured of Cushing's disease, and that this impaired pituitary response to CRH is not reversible by 1 week of pulsatile hCRH administration.