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7 alpha- and 7 beta-Carboxymethylderivatives of cortisol, corticosterone and deoxycorticosterone have been synthetized. After coupling to bovine serum albumin, they were used to elicit antibodies in rabbits. Highly specific antisera were obtained which may possibly be used for a direct radioimmunoassay of these steroids in human and rodent plasma. In the case of the derivatives of cortisol and corticosterone and stereoisomery of the coupling had an effect on the affinity and the specificity of the antisera. In all immunized rabbits the antisera obtained with the 7 alpha-derivative had a higher affinity and a narrower specificity than the antiserum obtained with the 7 beta-derivative.  相似文献   

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In vitro aldosterone, deoxycorticosterone, corticosterone and cortisol production of human adrenocortical cells derived from adenomas (Conn's syndrome, Cushing's syndrome), from hyperplastic adrenals (Cushing's syndrome) and from adrenals surrounding aldosteronoma are described. Cells from adenomas causing either Cushing's syndrome or Conn's syndrome harboured the highest basal and ACTH-stimulated corticosteroid production. Adrenocortical cells derived from micronodular hyperplasia causing Cushing's syndrome and cells from cortisol producing adenoma displayed predominantly cortisol and corticosterone secretion both under basal conditions and following stimulation with ACTH. Aldosteronoma cells showed highly variable aldosterone, deoxycorticosterone, corticosterone and cortisol response to ACTH. However, in aldosteronoma cell suspensions, the basal and ACTH-stimulated ratios of aldosterone to cortisol were increased when compared to ratios of steroids produced by cells from other adrenal tissues. Chronic treatment with spironolactone of patients with Conn's syndrome before surgery was associated with a decreased ratio of aldosterone to corticosterone, revealing that 18-hydroxylase in aldosteronoma cells may be inhibited during long-term therapy. Non-tumorous cells isolated from adrenals surrounding aldosteronoma displayed less aldosterone prior to and after stimulation with ACTH than aldosteronoma cells.  相似文献   

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Extinction behavior was nearly absent in rats adrenalectomized one hour prior to forced extinction of a passive avoidance response. A low dose of corticosterone administered immediately after adrenalectomy normalized extinction behavior. Progesterone, 11-deoxycorticosterone and the synthetic glucocorticoid dexamethasone were not effective at the same or ten times higher doses. Instead, pre-treatment with these steroids prevented the normalizing effect of corticosterone on extinction behavior. These characteristics of steroid effects on behavior correspond to the strict specificity of the corticosterone receptor system in hippocampal neurons. The agonist or antagonist interaction of naturally occurring adrenal steroids with brain cells may serve behavioral adaptation.  相似文献   

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The dissociation of estradiol complexes with specific binding proteins of blood sera from 5-day-old and pregnant rats was studied. Two types of complexes differing essentially in their dissociation rates were obtained. The decomposition of fast-dissociating complexes was completed within 30 s. Two classes of corticosterone-binding sites, one of which could form highly labile complexes, were revealed.  相似文献   

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To test whether progesterone also influences the serum ceruloplasmin activity (CSA) like estrogen (in the form of ethinyl estradiol and stilbestrol) and oral contraceptives containing both estrogenic and progestogen components, and if so to find out the relative influence of estrogen and progesterone, rabbits were treated with progesterone, estradiol dipropionate, a combination of these two and diethyl stilbestrol, and the SCA was estimated. Progesterone caused 194 and 262% increase in two and three weeks respectively. (p less than .001) Estradiol dipropionate failed to increase SCA, while diethyl stilbesterol caused an increase similar to that of progesterone.  相似文献   

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We are now showing that cultured human melanoma cells can synthesize steroids such as corticosterone from progesterone or deoxycorticosterone. Corticosterone production is strongly responsive to deoxycorticosterone substrate addition (12-fold increase), but unresponsive to the adrenal stimulating factors ACTH and angiotensin II. This is the first demonstration that skin cells (malignant melanocytes) have the capability to synthesize 11-deoxycorticosterone, corticosterone, and 18-hydroxydeoxycorticosterone.  相似文献   

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Ovarian changes determined by daily transrectal ultrasonic scanning, and its correlation with serum progesterone (P4) and estradiol (E2) concentrations were studied in seven cyclic Saanen goats. Estrous cycles were synchronized with 2 injections of a PGF2 alpha analogue 9 d apart. All follicles > or = 2 mm in diameter and CL were measured each day. One goat showed a longer interestrous interval, associated with development of a cystic-luteinized structure. The mean interovulatory interval for the other 6 goats was 20.8 +/- 0.4 d. The incidence of goats with 4, 3, and 2 follicular waves was 3, 1 and 2 respectively; follicular waves emerged on Days 0.5 +/- 0.6, 7.2 +/- 0.7, 10.7 +/- 0.5 and 13.7 +/- 0.8 for Wave 1, 2, 3 and the Ovulatory wave, respectively. The largest follicle of Wave 2 was smaller (4.9 +/- 0.1 mm) than the largest follicles of Wave 3 (6.2 +/- 0.1 mm; P < or = 0.01) and of the Ovulatory wave (7.0 +/- 0.5 mm; P < or = 0.01), and tended to be smaller than the largest follicle of Wave 1 (6.3 +/- 0.6 mm; P < or = 0.09). Interval between emergence of Wave 1 and Wave 2 was longer than interval between emergence of Wave 2 and Wave 3 (7.3 +/- 0.9 d vs 4.0 +/- 0.4 d; P < or = 0.01), and between Wave 3 and the Ovulatory wave (3.8 +/- 1.1 d; P < or = 0.05). Two days before ovulation, the diameter of the ovulatory follicle was larger (P < or = 0.01) than the first subordinate follicle. Serum E2 concentrations increased from the day of ovulation (2.7 +/- 0.3 pg/mL) to Day 2 (7.6 +/- 0.9 pg/mL; P < or = 0.01), associated with the early-mid growing phase of the largest follicle of Wave 1, and then decreased to basal levels on Day 5 (P < or = 0.01) and peaked again (16.5 +/- 2.4 pg/mL) 2 d before ovulation. The CL were detected ultrasonically on Day 3 post ovulation and attained a mean maximum diameter of 13.5 +/- 0.8 mm between Days 8 and 14. The following characteristics were observed: 1) ovarian follicular development in goats is wave-like; 2) increased P4 concentrations may be promoting follicular wave turnover; 3) it is suggested that the presence of follicular dominance and the production of E2 are different among waves. While in Wave 1 and in the Ovulatory wave, follicular dominance is present and production of E2 is consistent, no changes in serum E2 concentrations were found in other stages of the interovulatory interval. In the intervening waves, no indicators of follicular dominance could be firmly documented.  相似文献   

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Regularly cyclic, middle-aged female rats exhibit a decreased incidence of fertility, and those females that are fertile produce small litters. These decreases in fertility and litter size are associated with reduced numbers of normal blastocysts formed and implanted, suggesting that pre- and/or peri-implantation failures may be the causes for these aging-related reproductive declines. The present study examined the relationships and influence of circulating estradiol (E2) and progesterone (P) levels on early embryonic development and implantation in middle-aged rats. Serial blood samples obtained from cannulated, middle-aged pregnant rats revealed minor decreases in plasma P and increases in E2 levels during Days 2-4 of pregnancy, compared to young pregnant rats, resulting in significantly (p less than 0.001) decreased plasma P/E2 ratios. These alterations in endogenous hormone secretion in middle-aged pregnant rats were associated with fewer normal blastocysts on Day 5 of pregnancy and reduced numbers of normally implanting embryos. Correlation analysis further revealed a significant (p less than 0.05) inverse relationship between mean circulating E2 levels and numbers of normal conceptuses on Day 12 of gestation. Moreover, s.c. administration of P implants (in Silastic) to middle-aged pregnant rats increased serum P levels by about 34-40 ng/ml, and significantly (p less than 0.05) reduced the incidence of abnormal embryos before implantation. In contrast, treatment with E2 minipumps produced a sustained rise in serum E2 (by about 7-15 pg/ml) and resulted in the complete absence of embryos in the reproductive tracts by Day 5 of pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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Aminoglutethimide (AG), an inhibitor of steroidogenesis, was administered s.c. to 5 groups of laying hens at a dose of 200 mg AG/kg body weight 9 h before expected midsequence ovulation. This dose has previously been demonstrated to consistently block ovulation. The injection of AG was followed by s.c. injections of: Group 1, 1.0 mg progesterone; Group 2, 0.1 mg estradiol-17 beta; Group 3, 1.5 mg corticosterone, all at 6 h prior to expected ovulation; Group 4, 1.0 mg testosterone at both 8 h and 5 h before expected ovulation; and Group 5, 25 micrograms of ovine luteinizing hormone (LH) at 8 and 50 micrograms ovine LH at 6 h before expected ovulation. For each group, 4 control hens were injected with AG and the appropriate vehicle. Blood samples were taken at 1- or 2-h intervals from the time of AG injection to the expected time of ovulation. The hens were killed 4 h after expected ovulation and examined for the occurrence of ovulation. In all hens injected with vehicle, ovulation and the preovulatory surges of progesterone, testosterone, estradiol-17 beta and LH were inhibited. The plasma concentration of corticosterone was not reduced following an injection of AG. Four of 6 hens ovulated in response to injection of ovine LH, although neither endogenous LH nor progesterone were released. Thus, LH appears to play a direct role in follicular rupture and extrusion of the ovum. The administration of progesterone induced a significant and prolonged rise in LH, restoring AG-blocked ovulation in all hens treated (n = 6). Injections of testosterone restored LH release in all hens and ovulation in 2 of 7 hens treated. Three of 7 hens ovulated in response to the corticosterone injection. A preovulatory rise in LH was not observed, indicating that corticosterone may exert its ovulation-inducing effect directly on the mature follicle. Estradiol-17 beta did not restore LH release or ovulation in any of the hens treated with AG.  相似文献   

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Proton magnetic resonance spectroscopy played a crucial role in the identification of a new corticosteroid, 18-hydroxycortisol, recently isolated from the urine of a patient with an aldosterone-producing adenoma. Mass spectrometric analysis and chemical degradative studies demonstrated an empirical formula of C21 H30 O6 corresponding to a diketopregnenetetrol and placed three of the four hydroxyl groups at the 11 beta, 18 and 21 positions. The first suggestion that the locus of the fourth hydroxyl was 17 alpha came from the n.m.r. spectrum in the form of negative evidence for proton linked to the carbon atom bearing this fourth hydroxyl. The n.m.r. spectral features of the 18-hydroxy derivatives of cortisol and corticosterone are compared. Both were found to exist in the 20, 18 cyclic hemiketal form.  相似文献   

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The effects of 30 min of exercise (74.1 +/- 3.0% (VO2), on the responses of progesterone (P), estradiol (E2), follicle stimulating hormone (FSH), and luteinizing hormone (LH) were investigated in 10 women. With such exercise significant increments occurred in P (37.6 +/- 9.5%) and E2 (13.5 +/- 7.5%) (P less than 0.05), whereas no changes were observed in FSH and LH (p greater than 0.05). Exercise in the luteal phase and during menses provoked similar changes in P, but E2 concentrations remained unchanged when exercise occurred during menses (p greater than 0.05). With 8-11 weeks of training the menstrual cycles were quite irregular and retesting of subjects in the same phase of the cycle was not possible. Yet, when subjects were retested after training, no changes occurred in P, E2 or LH (p greater than 0.05) but a decrement did occur in FSH (p less than 0.10). Thus, heavy exercise in untrained subjects provokes significant increments in ovarian hormones, whereas no such increments are observed in trained subjects exercising at the same absolute workload.  相似文献   

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本文旨在通过探讨新生儿李斯特菌病的临床特点、治疗及预后,明确母体危险因素,为新生儿产单核细胞李斯特菌(下称李斯特菌)感染的临床诊断和治疗提供依据。回顾性分析2011年5月-2018年4月西北妇女儿童医院新生儿科诊治的18例李斯特菌感染新生儿及其母亲的发病情况、临床表现、实验室指标、影像学检查、治疗及预后,发现18例产妇中15例有临床症状,以发热及不规则腹痛最为常见;患儿中13例有临床症状,多数表现为呼吸窘迫和发热;89%患儿发生血流感染(61%为化脓性脑膜炎、28%为肺炎);影像学检查提示,存活患儿中56%有神经系统后遗症,50%可能有先天性心脏病。14例在明确李斯特菌感染后调整抗生素治疗,所有产妇经治疗均预后良好;患儿除1例放弃治疗、3例要求出院外,其余14例均痊愈或好转出院。新生儿李斯特菌感染是一种严重的感染性疾病,因此对有发热、腹痛及早产症状的孕妇,应警惕李斯特菌感染,尽早进行病原学检测和目标性治疗,以改善预后。  相似文献   

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