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71.
French JA Fite JE Jensen H Oparowski K Rukstalis MR Fix H Jones B Maxwell H Pacer M Power ML Schulkin J 《American journal of primatology》2007,69(8):877-889
Corticotropin-releasing hormone (CRH) has multiple roles in coordinating the behavioral and endocrine responses to a host of environmental challenges, including social stressors. In the present study we evaluated the role of CRH in mediating responses to a moderate social stressor in Wied's black tufted-eared marmosets (Callithrix kuhlii). Male and female marmosets (n=14) were administered antalarmin (a selective CRH-1 receptor antagonist; 50 microg/kg, p.o.) or vehicle in a blind, counterbalanced, crossover design. One hr after treatment, marmosets were separated from long-term pairmates and then housed alone in a novel enclosure for 7 hr. Behavior was recorded during separation and upon reunion with the partner, and urine samples for cortisol assay collected before, during, and after the intervention. Separation from partners elevated urinary cortisol concentrations over baseline for both conditions, but antalarmin treatment reduced the magnitude of the elevation. Antalarmin also lowered rates of behavioral patterns associated with arousal (alarm and "e-e" vocalizations, object manipulate/chew), but had no effect on contact calls, locomotory activity or alertness. Although most patterns of social behavior upon reunion with the partner were not affected by antalarmin, antalarmin-treated marmosets displayed more sexual behavior (mounts and copulations) upon reunion. These data indicate that antagonism of the CRH-1 receptor acts to reduce the magnitude of both endocrine and behavioral responses to a moderate social stressor without causing any overall reduction in alertness or general activity. This supports the hypothesis that CRH, acting through its type 1 receptor, is involved in coordinating the responses to anxiety-producing events. These results further suggest that the marmoset is a useful model for exploration of the role of CRH in mediating the behavioral and neuroendocrine responses to psychosocial stressors, particularly in the context of heterosexual social relationships. 相似文献
72.
We investigated the long-term effects of divorce and early separation from one parent on HPA axis reactivity, in young adults without psychopathology. Participants were 44 young subjects, 22 whose parents divorced before they reached age 10, and 22 controls. Psychiatric symptomatology was measured with the Brief Symptom Inventory (BSI), family perceived stress by the Dyadic Adjustment Scale (DAS), and bonding by the Parental Bonding Instrument (PBI). Assessment of HPA axis function included baseline morning cortisol and ACTH and cortisol response to a CRH stimulation test. No baseline or stimulated group differences were observed for ACTH. Cortisol levels were consistently but insignificantly lower in the divorce group throughout the CRH stimulation reaching statistical significance only at 5 min (p<0.03). Group by time effect reached a trend level (p<0.06). A correlation was found between psychiatric symptomatology and PBI scores; however, both parameters did not correlate with HPA axis activity. A significant correlation was found between DAS scores and ACTH. A regression model revealed a contributing effect for both family stress and child-parent bonding to stimulated ACTH levels. These preliminary findings suggest that even in the absence of adult psychopathology, a history of childhood separation from one parent due to divorce may lead to detectable, albeit mild, long-term alterations in HPA axis activity. Furthermore, they suggest that level of stress at home and parental bonding are important determinants of this effect. It is likely that divorce has significant and sustained effects on children's HPA axis only in the context of a traumatic separation. 相似文献
73.
74.
Neoplastic plant-tissue formation, termed crown gall disease, is induced on infection with Agrobacterium tumefaciens. The tumorous tissues develop an extensive vascular system, with a venation pattern distinct from that of native host plants.
We report here that the plant-tumorigenic 6b gene of the A. tumefaciens strain AKE10 is capable of inducing extensive vein formation in transgenic tobacco seedlings with distinct pattern formation.
Unlike the wild-type cotyledons, transgenic cotyledons had wavy and striate veins depending on the extent of severity of leaf
morphology. Graph analysis of the transgenic cotyledonous vein patterns revealed an increase in the number of branch points
of veins, end-points of veins, and areas surrounded by the veins. Histological analysis showed abnormal tissue growth on the
abaxial side of the cotyledon blades and continual formation of adventitious veins. These adventitiously formed veins included
inverted dorso-ventrality and formation of a radial axis. 相似文献
75.
Tissue morphogenesis depends on precise regulation and timely co-ordination of cell division and also on the control of the direction of cell division. Establishment of polarity division axis, correct alignment of the mitotic spindle, segregation of fate determinants equally or unequally between daughter cells, are essential for the realization of oriented cell division. Furthermore, oriented cell division is regulated by intrinsic cues, extrinsic cues and other cues, such as cell geometry and polarity. However, dysregulation of cell division orientation could lead to abnormal tissue development and function. In the present study, we review recent studies on the molecular mechanism of cell division orientation and explain their new roles in skin repair and regeneration. 相似文献
76.
Ming‐Dong Zhang Amit Zeisel André Calas Marc Landry Matthew Fuszard Sally L Shirran Robert Schnell Árpád Dobolyi Márk Oláh Lauren Spence Jan Mulder Henrik Martens Miklós Palkovits Mathias Uhlen Harald H Sitte Catherine H Botting Ludwig Wagner Sten Linnarsson Tibor Harkany 《The EMBO journal》2015,34(1):36-54
77.
78.
Risk factors for suicidal behaviors are partly heritable, including genetic variants that drive diathesis-stress in addition to, or by interaction with, exposure to certain stressful life events (SLEs). Hypothalamic-pituitary-adrenal (HPA) axis regulatory genes are candidates for association with suicide as well as its endophenotypes. Using a family-based design of offspring who attempted suicide (SA) and both parents, we investigated gene-environment interactions (G×Es) of SLE exposures with single nucleotide polymorphisms (SNPs) in corticotropin-releasing hormone receptor-1 (CRHR1), a major HPA axis regulatory gene. We observed a novel G×E among predominantly female SA between 5'-SNP rs7209436 and childhood/adolescence physical assault or attack (PA), as well as a second novel and male-specific G×E between 3'-SNP rs16940665 and adulthood PA exposure. A third male-specific G×E previously reported by us among depressed SA, between SNP rs4792887 and cumulative SLEs, was also further confirmed. The two novel G×Es presented here shared the SA characteristic of aggression, while showing differences on other aspects of SA heterogeneity. We conclude that different SA subjects were observed to differentially associate with two novel G×Es involving exposures to PA with different life timing and SNPs located in opposite ends of CRHR1. Concerning sex differences, we observed three subsets of distinct male SA that associated with each of the three observed G×Es, whereas female SAs were affected by only one of the G×Es. These results are consistent with a diathesis-stress model of suicidal behavior and may help to explain SA heterogeneity. 相似文献
79.
目的:研究气温骤升导致高血压大鼠发生脑梗塞的神经内分泌机制。方法:采用易卒中型肾血管性高血压(RHRSP)模型,放置于人工模拟气温骤升的高温环境中诱发脑梗塞,检测高温刺激前后大鼠ACTH、CORT、TSH、T3、T4的变化。结果:突然升温使生理组大鼠ACTH和CORT水平表现升高的趋势。模型组高血压大鼠CORT、TSH、T3、T4水平在升温中均呈现升高趋势,但是ACTH水平却明显降低(P〈0.05)。升温后发生脑梗塞大鼠的ACTH和T4水平与升温前比明显下降(P〈0.01),而TSH水平明显高于升温前水平(P〈0.05),T3水平不变。结论:高血压机体应激反应系统紊乱,甲状腺刺激素和肾上腺皮质激素的异常波动,是突然高温促发高血压机体脑梗塞发病的重要神经内分泌机制。 相似文献
80.
目的:观察维吾尔药(维药)神香草对哮喘大鼠模型神经内分泌免疫网络若干组分的影响。方法:取雄性健康Wistar大鼠50只,随机分为正常对照组,哮喘模型组,神香草低、中、高剂量治疗组。采用致敏和雾化的方法制备哮喘模型。采用酶联免疫吸附试验(ELISA)方法检测血清中白介素-4(IL^4)、白介素-6(IL-6)、干扰素-γ(IFN-γ)、皮质酮(CORT)水平;放免法检测血浆中促肾上腺皮质激素(ACTH)的含量;采用实时定量-聚合酶链反应(RT—PCR)法测定下丘脑促肾上腺皮质激素释放激素(CRH)mRNA表达水平。结果:哮喘反复发作时,大鼠下丘脑-垂体-肾上腺(HPA)轴紊乱,哮喘大鼠下丘脑CRHmRNA表达和血浆ACTH无明显变化,实验各组血清CORT水平升高(P〈0.05),神香草高剂量组血清CORT含量高于低剂量组(P〈0.05)。细胞因子IFN-γ无明显变化,IL-6、IL-4有下降趋势(P〈0.05)。结论:哮喘反复发作的大鼠存在NEI网络的紊乱;神香草可以增强下丘脑.垂体.肾上腺皮质(HPA)轴的功能,改善细胞因子的平衡。这些可能是其治疗哮喘的机制之一。 相似文献