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991.
急性脑死HPA轴激素与胰腺内分泌变化的研究 总被引:5,自引:1,他引:4
目的:研究急性脑梗死(ACI)下丘脑-垂体-肾上腺(HPA)轴激素与胰腺内分泌的变化,以探讨其发病机理。方法:采用施放免疫分析法(RIA)分别对151例ACI患者进行CRH(促肾上腺皮质激素释放激素)、ACTH(促肾上腺皮质激素)、CS(皮质醇)、INS(胰岛素)及GLC(胰高血糖素)入院时始发状态血液检测,并与60例年龄相仿健康人组作对照。结果:ACI者轴激素显著高于健康正常人组(P〈0.01~ 相似文献
992.
The association between additional co-morbid axis I disorders and the following 28-month course of drinking and mental distress was explored in a nation-wide representative sample (N = 100) of treatment-seeking alcoholics with antisocial personality disorder (ASPD). Diagnoses at admission were assessed with the Diagnostic Interview Schedule and follow-up status was assessed with a questionnaire and from informants. Only 24% had no additional diagnoses, 39% had an affective disorder, 43% panic/agoraphobia, 61% other anxiety disorders, and 47% were polysubstance abusers. Polysubstance abusers had more prior admissions, and were more often involved in fights, while additional anxiety disorder was associated with lower prevalence of drunken driving arrests. Relapse (87%) was best predicted by the number of prior admissions (odds ratio [OR] = 1.3), while affective disorders reduced the risk of relapse (OR = 0.2). Readmissions (55%) were least common among those with affective disorders (44%). Identifying axis I diagnoses, and in particular affective disorders among treatment-seeking ASPD alcoholics, is of substantial importance both in research and clinical practice. 相似文献
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994.
Central autonomic and neuroendocrine activities are important components of the host response to bacterial inflammation. We demonstrate that intravenous infusion of γ2-melanocyte-stimulating hormone (γ2-MSH), a potent autonomic regulating peptide, prevents lipopolysaccharide (LPS)-induced hypotension and tachycardia, and modulates the ACTH response to endotoxin. In the hypothalamic paraventricular nucleus, a major neuroendocrine and autonomic center, γ2-MSH inhibits LPS-induced increases in CRF mRNA levels, but does not suppress LPS-augmented arginine vasopressin heteronuclear RNA expression. In the locus coeruleus, a brainstem noradrenergic center, γ2-MSH inhibits LPS-induced increases in tyrosine hydroxylase mRNA levels. γ2-MSH inhibits LPS-induced IL-1β gene expression in the brain, pituitary and thymus, and prevents increases in plasma NO levels. These findings reveal that γ2-MSH attenuates systemic inflammatory responses to endotoxin and suggest that modulation of central autonomic and neuroendocrine activities by γ2-MSH contributes to its anti-inflammatory effects. 相似文献
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996.
目的探讨"怒"模型大鼠胸腺细胞中T细胞免疫球蛋白和ITIM结构域蛋白(TIGIT)及其配体CD155和血清促肾上腺皮质激素释放激素(CRH)、促肾上腺皮质激素(ACTH)、白细胞介素-2(IL-2)、白细胞介素-10(IL-10)表达情况,以及这些指标与胸腺细胞凋亡的相关性。方法将48只Wistar雄性大鼠随机分成对照组、模型7 d组、模型14 d组、模型21 d组,每组12只。除对照组外,其余各组以“社会隔离法”结合足底电击法复制精神应激“怒”模型大鼠。实验后测定大鼠体质量和胸腺指数,以苏木精-伊红(HE)染色观察大鼠胸腺组织的形态学改变,采用免疫印迹法检测各组大鼠胸腺细胞中TIGIT、CD155蛋白的表达水平,采用Tunel法检测胸腺细胞凋亡情况,采用酶联免疫吸附试验测定血清CRH、ACTH、IL-2、IL-10水平。结果实验后,4组大鼠体质量较试验前1 d升高(P<0.05),且“怒”模型各组大鼠体质量均低于对照组(P<0.05);实验后“怒”模型各组大鼠胸腺指数均低于对照组(P<0.05)。HE染色光学显微镜下(×400)可见“怒”模型各组大鼠大鼠胸腺皮质组织结构出现不同程度的损坏,幼稚T细胞布排紊乱无序或呈“条索状”堆积,细胞间隙缩小,细胞数量较对照组降低,细胞核染色变浅,呈淡紫色,并出现不同程度核固缩、核分裂、细胞溶解等凋亡细胞增多现象。4组大鼠胸腺细胞TIGIT蛋白表达水平比较,对照组<模型21 d组<模型14 d组<模型7 d组,其中模型7 d组、14 d组与其他各组胸腺细胞TIGIT蛋白表达水平差异均有统计学意义(P<0.05);“怒”模型各组大鼠胸腺细胞CD155蛋白表达水平高于对照组,差异均有统计学意义(P<0.05)。“怒”模型各组胸腺组织凋亡细胞吸光度高于对照组,差异有统计学意义(P<0.05)。模型7 d组、模型14 d组血清CRH、ACTH水平高于对照组及模型21 d组(P<0.05);“怒”模型各组IL-2水平低于对照组(P<0.05),且模型7 d组、模型14 d组低于模型21 d组(P<0.05);“怒”模型各组IL-10水平高于对照组(P<0.05),且模型14 d组高于模型7 d组及模型21 d组(P<0.05)。Pearson相关分析结果显示,TIGIT表达水平与CD155、ACTH、CRH及胸腺细胞凋亡程度呈正相关(P<0.05),与IL-2呈负相关(P<0.05),与IL-10及胸腺指数无相关性(P>0.05);CD155表达水平与TIGIT及胸腺细胞凋亡程度呈正相关(P<0.05),与IL-2呈负相关(P<0.05),与ACTH、CRH、IL-10及胸腺指数无相关性(P>0.05)。结论“怒”应激状态下,胸腺出现萎缩及凋亡细胞增多现象,可能是TIGIT-CD155与下丘脑-垂体-肾上腺轴、IL-10、IL-2共同作用所致,该研究为“怒”应激致使免疫损伤及疾病发生发展提供理论依据。 相似文献
997.
Edda Russo Camila Fiorindi Francesco Giudici Amedeo Amedei 《World journal of hepatology》2022,14(2):372-385
Hepatocellular carcinoma (HCC) is the most prevalent primary malignancy in patients suffering from chronic liver diseases and cirrhosis. Recent attention has been paid to the involvement of the gut-liver axis (GLA) in HCC pathogenesis. This axis results from a bidirectional, anatomical and functional relationship between the gastrointestinal system and the liver. Moreover, the complex network of interactions between the intestinal microbiome and the liver plays a crucial role in modulation of the HCC-tumor microenvironment, contributing to the pathogenesis of HCC by exposing the liver to pathogen-associated molecular patterns, such as bacterial lipopolysaccharides, DNA, peptidoglycans and flagellin. Indeed, the alteration of gut microflora may disturb the intestinal barrier, bringing several toll-like receptor ligands to the liver thus activating the inflammatory response. This review explores the new therapeutic opportunities that may arise from novel insights into the mechanisms by which microbiota immunomodulation, represented by probiotics, and prebiotics, affects HCC through the GLA. 相似文献
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999.
The early life period is crucially important to how the individual develops, and environmental and lifestyle challenges during this time can lead to lasting programming effects on the brain and immune system. In particular, poor diet in early development can lead to long-term negative metabolic and cognitive outcomes, with those who over-eat in early development being at risk of obesity and poor learning and memory throughout their adult lives. Current research has identified a neuroinflammatory component to this metabolic and cognitive programming that can potentially be manipulated to restore a healthy phenotype. Thus, early life over-feeding in a rat model leads to microglial priming and an exacerbated microglial response to immune challenge when the rats reach adulthood. Microglial responses to a learning task are also impaired. To specifically investigate the role of microglia in these programming effects our group has developed a novel transgenic rat with a diphtheria toxin receptor insertion in the promoter region for the Cx3cr1 gene, expressed on microglia and monocytes; allowing us to conditionally ablate microglia throughout the brain. With this model we reveal that microglia have a direct role in regulating feeding behavior and modifying cognition, but are not likely to be the sole mechanism by which early life overfeeding confers lasting neuroimmune and cognitive effects. Additional work implicates changes to the hypothalamic-pituitary-adrenal axis in this. Together these data highlight the importance of dietary choices in early life and the potential for positive interventions targeting the neuroimmune and neuroendocrine stress systems to reverse such programming damage. 相似文献
1000.
RFamide-related peptides (RFRPs) have long been identified as inhibitors of the hypothalamus-pituitary-gonad axis in mammals. However, less progress has been made in the detailed roles of RFRPs in the control of LH secretion. Recent studies have suggested that RFRP-3 neurons in the hypothalamus can regulate the secretion of LH at different levels, including kisspeptin neurons, GnRH neurons, and the pituitary. Additionally, conflicting results regarding the effects of RFRP-3 on these levels exist. In this review, we collect the latest evidence related to the effects of RFRP-3 neurons in regulating LH secretion by acting on kisspeptin neurons, GnRH neurons, and the pituitary and discuss the potential role of the timely reduction of RFRP-3 signaling in the modulation of the preovulatory LH surge. 相似文献