ACTH increases noradrenaline release in the rabbit heart

Summary The effects of ACTH on the release of noradrenaline and the increase of heart rate produced by sympathetic nerve stimulation (1 Hz) were studied in isolated perfused rabbit hearts. ACTH-(1–24) 0.1–100 nmol/l increased the stimulation-evoked overflow of noradrenaline concentration-dependently, reversibly and up to two-fold. The basal outflow of noradrenaline, the basal heart rate and the stimulation-evoked increase in heart rate were not changed. Human ACTH-(1–39) also increased the evoked overflow of noradrenaline. The effect of ACTH-(1–24) 0.3 nmol/l persisted after blockade of -adrenoceptors with propranolol and blockade of neuronal catecholamine uptake by cocaine. ACTH-(1–24) 3 nmol/l did not change the removal of noradrenaline from the perfusion fluid, when hearts were perfused with medium containing 59 nmol/l noradrenaline. The results show that ACTH increases the action potential-evoked release of noradrenaline from cardiac postganglionic sympathetic neurones, probably by activating specific presynaptic ACTH receptors. The high potency of ACTH suggests that these presynaptic receptors may be activated in vivo by circulating ACTH under certain pathophysiological conditions.Send offprint requests to B. Szabo at the above address     

22例皮质醇增多症的临床研究

目的：探讨皮质醇增多症的临床表现和内分泌检查等辅助检查的意义.方法：从年龄、性别、病程及实验室检查等方面,观察22例不同原因所致皮质醇增多症患者不同的临床表现和测定实验室检查指标.结果：22例中诊断库欣病（增生型）14例[63.6％,其中13例（92.9％）得到MRI检查证实],肾上腺腺瘤6例[27.3％,均得到MRI检查证实（100％）],另有肾上腺结节样增生1例（4.5％）,异位ACTH综合征1例（4.5％）.临床表现：按出现的频率前4位依次为,库欣病：高血压（100％）、满月脸（92.9％）、向心性肥胖（85.7％）、多血质（85.7％）,肾上腺腺瘤：高血压（100％）、满月脸（100％）、向心性肥胖（100％）、多血质（83.3％）.实验室检查：小剂量地塞米松不能抑制：库欣病与肾上腺腺瘤均为100％.结论：根据高血压、满月脸、向心性肥胖,小剂量地塞米松抑制试验和MRI检查可诊断绝大多数皮质醇增多症.     

急性脑缺血鼠下丘脑-垂体-肾上腺轴的活动特征

目的探讨急性脑缺血（ＡＣＩ）及再灌注过程中边缘系统促肾上腺皮质释放激素（ＣＲＨ）ｍＲＮＡ转录与血浆促肾上腺皮质激素（ＡＣＴＨ）应变调控作用的机制。方法利用鼠大脑中动脉阻塞（ＭＣＡＯ）模型，应用原位杂交和放射免疫分析法，监测对照组和缺血组鼠脑颞叶、海马和下丘脑的ＣＲＨｍＲＮＡ转录水平和血浆ＡＣＴＨ的活性变化。结果ＡＣＩ组缺血及再灌注各期颞叶、海马和下丘脑等多部位ＣＲＨｍＲＮＡ转录显著活跃，血浆ＡＣＴＨ水平同步升高，两者间密切相关。结论缺血再灌注各期，广泛脑区特别是边缘系统和下丘脑ＣＲＨ启动，合成活跃，是导致ＡＣＩ的中枢神经系统调控紊乱的关键环节和加重缺血神经元损伤的一个重要物质基础。显然，干预ＣＲＨ启动、合成与释放是减轻应激反应和保护缺血神经元的重要途径之一。     

促肾上腺皮质激素释放因子受体2在溃疡性结肠炎中的表达

目的观察促肾上腺皮质激素释放因子受体2（CRFR2）在溃疡性结肠炎（UC）中的表达情况,及其与细胞间黏附分子-1（ICAM-1）、核因子-KB（NF-JcB）p65和白细胞介素-6（IL-6）的关系,探讨其在UC中的作用。方法免疫组织化学法检测UC活动组30例、缓解组30例和30例正常对照组的结肠黏膜中cRFR2、ICAM-1、NF-KBp65的表达情况,ELISA方法检测各组血清中IL-6水平。结果CRFR2在UC活动组肠黏膜组织中的表达明显高于缓解组和对照组（P〈0．05）,而在UC缓解组和对照组之间的表达差异无统计学意义（P〉0．05）。CRFR2在肠黏膜组织中的表达与NF-xBp65、ICAM-1的表达及血清中IL-6水平具有明显相关性（P〈0．05）。结论活动期UC患者的CRFR2的表达明显升高,提示其在UC发病中可能起促炎作用。     

人增生性瘢痕组织内下丘脑—垂体—肾上腺皮质轴成分的表达

目的 探讨增生性瘢痕组织中下丘脑-垂体-肾上腺皮质(HPA)轴成分的表达及意义.方法 应用实时荧光定量PCR法,检测人增生性瘢痕(12例)和正常皮肤(7例)组织中HPA轴的活性物质促肾上腺皮质素释放激素(CRH)、促肾上腺皮质素释放激素受体1(CRH-R1)、阿片-促黑素细胞皮质素原(POMC)、黑素皮质素受体2(MC-2R)以及糖皮质激素受体α(GR-α)的mRNA表达差异,免疫组织化学法观察CRH、CRH-R1、促肾上腺皮质激素(ACTH)、MC-2R以及GR-α的分布差异.对数据进行独立样本t检验. 结果 PCR结果显示,增生性瘢痕组织标本中CRH、CRH-R1、POMC及GR-α的mRNA表达分别为3.1±0.8、0.05±0.03、0.020±0.007、0.0000±0.0010,均低于正常皮肤组织的20.6±4.7、0.30±0.12、0.060±0.020、0.0200±0.0070,差异有统计学意义(t值为2.10-4.75,P值均小于0.05);但2种组织中MC-2R mRNA表达水平接近(t=1.48,P=0.15).免疫组织化学法检测结果显示,CRH,CRH-R1、ACTH、MC-2R以及GR-α分布于瘢痕组织的表皮基底层、真皮层的Fb和汗腺管壁中.在正常皮肤组织中阳性细胞除分布于上述部位外,还可见于毛囊和皮脂腺. 结论 增生性瘢痕形成与组织中HPA轴的活性物质表达降低有关.     

Adrenocortical reserve of neonates born of long-term,steroid-treated mothers

Since corticosteroids have been shown to be transferred across the human placenta, prolonged administration of these drugs during gestation could be expected to suppress the response of the neonatal adrenal gland. Plasma cortisol levels, before and 30 min after the injection of ACTH (36 g/kg), were determined in six neonates who were exposed in utero to prolonged maternal administration of prednisone. The basal plasma cortisol levels of these neonates (6.15±2.57 g%; mean±SEM) were similar to values obtained in eight healthy neonates (5.19±1.36g%). The increment of cortisol levels after ACTH stimulation (16.4±2.07 g%) of the study patients was larger (P<0.01) than the change (10.3±0.82 g%) observed in six older controls. These results indicate a normal neonatal adrenal reserve after prolonged exposure to corticosteroids during fetal life.     

血浆促肾上腺皮质激素释放激素与妊娠期疾病关系的临床研究

目的:探讨治疗早产药物,早产、贫血、肝功能损害及妊娠期胆汁淤积症对妊娠期血浆促肾上腺皮质激素释放激素(CRH)水平的影响。方法:以放射免疫方法测定正常妊娠以及早产等妊娠期疾病时母体CRH水平的变化。结果:各孕周早产孕妇血浆CRH较正常对照孕妇显著升高(P<0.05)。经有效药物治疗后,血浆CRH明显回落。贫血、肝功能损害及足月妊娠合并胆汁淤积症可使血浆CRH水平升高(P<0.05)。孕37周前妊娠合并胆汁淤积症对血浆CRH水平无影响(P>0.05)。结论:妊娠期血浆CRH水平与早产关系密切,有可能成为预测早产的有效指标。以血浆CRH水平预测早产时,应注意排除贫血及肝功能损害的影响。     

Time- and dose-dependent effects of corticotropin releasing factor on cerebral glucose metabolism in rats

Summary. The time course and the relation to dose of locomotor activity and of the regional cerebral metabolic rates for glucose (rCMRglc) were measured in freely moving Sprague-Dawley rats after intracerebroventricular administration of ovine corticotropin releasing factor (oCRF). Motor activity was determined using a familiar photocage cell. rCMRglc was measured, using the quantitative autoradiographic [¹⁴C]2-deoxyglucose procedure, in 73 brain regions at 10, 30, 90 and 180 min after administration of oCRF 10 μg and at 90 min after oCRF 0.1, 1 and 100 μg. oCRF 10 μg increased motor activity in a sustained fashion and increased rCMRglc with different time courses throughout brain regions. In cerebellar regions rCMRglc increases peaked at 90 min and were sustained up to 180 min. In non-cerebellar regions rCMRglc increases peaked at 90 min but declined thereafter. At lower doses (0.1 and 1 μg) oCRF increased rCMRglc in fewer brain regions (1 and 5 regions affected, average increases 1% and 7%) including cerebellar areas and brainstem sensory nuclei and decreased rCMRglc in medial prefrontal cortex. At the highest dose (100 μg) oCRF induced large and widespread rCMRglc increases in cerebellar, brainstem, hypothalamic, limbic and neocortical areas (40 brain regions affected, average increase 32%). The findings indicate that cerebellar areas and brainstem nuclei are highly sensitive to oCRF and may mediate oCRF autonomic and behavioral effects.