Animals ; Mice ; Corticotropin-Releasing Hormone/metabolism* ; Neurons/metabolism* ; Brain/metabolism*

Adverse experiences in early life have long-lasting negative impacts on behavior and the brain in adulthood, one of which is sleep disturbance. As the corticotropin-releasing hormone (CRH)-corticotropin-releasing hormone receptor 1 (CRHR1) system and nucleus accumbens (NAc) play important roles in both stress responses and sleep-wake regulation, in this study we investigated whether the NAc CRH-CRHR1 system mediates early-life stress-induced abnormalities in sleep-wake behavior in adult mice. Using the limited nesting and bedding material paradigm from postnatal days 2 to 9, we found that early-life stress disrupted sleep-wake behaviors during adulthood, including increased wakefulness and decreased non-rapid eye movement (NREM) sleep time during the dark period and increased rapid eye movement (REM) sleep time during the light period. The stress-induced sleep disturbances were accompanied by dendritic atrophy in the NAc and both were largely reversed by daily systemic administration of the CRHR1 antagonist antalarmin during stress exposure. Importantly, Crh overexpression in the NAc reproduced the effects of early-life stress on sleep-wake behavior and NAc morphology, whereas NAc Crhr1 knockdown reversed these effects (including increased wakefulness and reduced NREM sleep in the dark period and NAc dendritic atrophy). Together, our findings demonstrate the negative influence of early-life stress on sleep architecture and the structural plasticity of the NAc, and highlight the critical role of the NAc CRH-CRHR1 system in modulating these negative outcomes evoked by early-life stress.
Animals ; Mice ; Corticotropin-Releasing Hormone/metabolism* ; Nucleus Accumbens/metabolism* ; Receptors, Corticotropin-Releasing Hormone/metabolism* ; Sleep ; Sleep Wake Disorders ; Stress, Psychological/complications*

High-altitude hypoxia can induce physiological dysfunction and mountain sickness, but the underlying mechanism is not fully understood. Corticotrophin-releasing factor (CRF) and CRF type-i receptors (CRFR1) are members of the CRF family and the essential controllers of the physiological activity of the hypothalamo-pituitary-adrenal (HPA) axis and modulators of endocrine and behavioral activity in response to various stressors. We have previously found that high-altitude hypoxia induces disorders of the brain-endocrine-immune network through activation of CRF and CRFR1 in the brain and periphery that include activation of the HPA axis in a time- and dose-dependent manner, impaired or improved learning and memory, and anxiety-like behavioral change. Meanwhile, hypoxia induces dysfunctions of the hypothalamo-pituitary-endocrine and immune systems, including suppression of growth and development, as well as inhibition of reproductive, metabolic and immune functions. In contrast, the small mammals that live on the Qinghai-Tibet Plateau alpine meadow display low responsiveness to extreme high-altitude-hypoxia challenge, suggesting well-acclimatized genes and a physiological strategy that developed during evolution through interactions between the genes and environment. All the findings provide evidence for understanding the neuroendocrine mechanisms of hypoxia-induced physiological dysfunction. This review extends these findings.
Altitude ; Animals ; Brain ; physiopathology ; Corticotropin-Releasing Hormone ; metabolism ; Hypothalamo-Hypophyseal System ; physiopathology ; Hypoxia ; physiopathology ; Pituitary-Adrenal System ; physiopathology ; Receptors, Corticotropin-Releasing Hormone ; metabolism ; Tibet

It is well established that increased excitability of the presympathetic neurons in the hypothalamic paraventricular nucleus (PVN) during hypertension leads to heightened sympathetic outflow and hypertension. However, the mechanism underlying the overactivation of PVN presympathetic neurons remains unclear. This study aimed to investigate the role of endogenous corticotropin-releasing factor (CRF) on the excitability of presympathetic neurons in PVN using Western blot, arterial blood pressure (ABP) and renal sympathetic nerve activity (RSNA) recording, CRISPR/Cas9 technique and patch-clamp technique. The results showed that CRF protein expression in PVN was significantly upregulated in spontaneously hypertensive rats (SHRs) compared with normotensive Wistar-Kyoto (WKY) rats. Besides, PVN administration of exogenous CRF significantly increased RSNA, heart rate and ABP in WKY rats. In contrast, knockdown of upregulated CRF in PVN of SHRs inhibited CRF expression, led to membrane potential hyperpolarization, and decreased the frequency of current-evoked firings of PVN presympathetic neurons, which were reversed by incubation of exogenous CRF. Perfusion of rat brain slices with artificial cerebrospinal fluid containing CRF receptor 1 (CRFR1) blocker, NBI-35965, or CRF receptor 2 (CRFR2) blocker, Antisauvagine-30, showed that blocking CRFR1, but not CRFR2, hyperpolarized the membrane potential and inhibited the current-evoked firing of PVN presympathetic neurons in SHRs. However, blocking CRFR1 or CRFR2 did not affect the membrane potential and current-evoked firing of presympathetic neurons in WKY rats. Overall, these findings indicate that increased endogenous CRF release from PVN CRF neurons enhances the excitability of presympathetic neurons via activation of CRFR1 in SHRs.
Rats ; Animals ; Rats, Inbred SHR ; Paraventricular Hypothalamic Nucleus/physiology* ; Receptors, Corticotropin-Releasing Hormone/metabolism* ; Rats, Inbred WKY ; Corticotropin-Releasing Hormone/metabolism* ; Neurons/physiology* ; Hypertension ; Sympathetic Nervous System

AIMTo research the effect of intermittent hypoxia during sleep on hypothalamus-pituitary-adrenal (HPA) axis and growth hormone (GH) level.

METHODSRats were respectively exposed to intermittent hypoxia, room air and continuous hypoxia, after 1 day, 3 days, 7 days and 30 days, mRNA levels of corticotropin-releasing hormone (CRH) and growth hormone releasing hormone (GHRH) in hypothalamus of rats were detected using RT-PCR, and the levels of CRH, GHRH, corticotropin(ACTH), cortex ketone, and growth hormone in plasma were measured.

RESULTSAfter 30 days, the CRH mRNA levels in rats hypothalamus which exposed to intermittent hypoxia were increased significantly than those exposed to continuous hypoxia as well as normal control but GHRH decreased, there was no difference between continuous hypoxia and normal control. After 1 day, 3 days, and 7 days, there was no difference between continuous hypoxia and intermittent hypoxia. After 30 days, the plasmic level of CRH,ACTH and cortex ketone increased, GHRH decreased and GH had no obvious change.

CONCLUSIONThe rats' HPA axis level increases and GHRH restrained with chronic intermittent hypoxia during sleep, feedback regulation disorders.

Animals ; Corticotropin-Releasing Hormone ; metabolism ; Growth Hormone ; metabolism ; Growth Hormone-Releasing Hormone ; metabolism ; Hypothalamo-Hypophyseal System ; Hypoxia ; Male ; Pituitary-Adrenal System ; Rats ; Rats, Wistar ; Sleep Apnea Syndromes ; metabolism

Drugs of abuse leads to adaptive changes in the brain stress system, and produces negative affective states including aversion and anxiety after drug use is terminated. Corticotrophin-releasing hormone (CRH) is the main transmitter in control of response to stressors and is neuronal enriched in the central amygdala (CeA), a sub-region of the extended amygdala playing an important role in integrating emotional information and modulating stress response. The effect of CRH neurons in CeA on the negative emotions on morphine naïve and withdrawal mice is unclear. Thus, we utilized CRH-Cre transgenic mice injected with AAV-mediated Designer Receptors Exclusively Activated By Designer Drugs (DREADDs) to chemogenetically manipulate CRH neurons in CeA. And methods of behavior analysis, including conditioned place aversion (CPA), elevated plus maze and locomotor activity tests, were used to investigate morphine withdrawal-induced negative emotions in mice. The results showed that, inhibiting CRH neurons of CeA decreased the formation of morphine withdrawal-induced CPA, as well as the anxiety level of CRH-Cre mice. Furthermore, specifically activating CRH neurons in CeA evoked CPA and anxiety of morphine naïve mice. Neither inhibiting nor activating CRH neurons had effects on their locomotor activity. These results suggest that CRH neurons in CeA are involved in the mediation of morphine withdrawal-induced negative emotion in mice, providing a theoretical basis for drug addiction and relapse mechanism.
Adrenocorticotropic Hormone ; Animals ; Central Amygdaloid Nucleus ; Corticotropin-Releasing Hormone ; metabolism ; Emotions ; physiology ; Mice ; Morphine ; metabolism ; Neurons ; metabolism

AIMTo investigate the influence of hypoxia on postnatal developing pattern of hypothalamic corticotropin releasing factor(CRF) and arginine vasopressin (AVP) in male and female neonatal rats.

METHODSThe hypoxia was simulated in hypobaric cabin. The content of AVP and CRF was assayed by RIA method.

RESULTSIt was showed the female rats had the similar developing process with male rats, either at 2300 m or at 5000 m altitude. When they developed at simulated 5000 m altitude, the content of their hypothalamic CRF was lower than that of control rats on postnatal day 21, while the content of AVP was higher than control on day 21 and 28.

CONCLUSIONMaybe the difference of the function between hypothalamic CRF and AVP or/and the incoherence of their developing stage contribute to their particular developing pattern at 5000 m altitude.

Altitude ; Animals ; Animals, Newborn ; Arginine Vasopressin ; metabolism ; Corticotropin-Releasing Hormone ; metabolism ; Female ; Hypothalamus ; metabolism ; Hypoxia ; Male ; Rats ; Rats, Wistar

Corticotropin releasing factor (CRF) is known to be involved in the stress response and in some degenerative brain disorders. In addition, CRF has a role as a neuromodulator in adult cerebellar circuits. Data from developmental studies suggest a putative role for CRF as a trophic factor during cerebellar development. In this study, we investigated the trophic role for CRF family of peptides by culturing cerebellar neurons in the presence of CRF, urocortin or urocortin II. Primary cell cultures of cerebella from embryonic day 18 mice were established, and cells were treated for either 1, 5 or 9 days with Basal Medium Eagles complete medium alone or complete medium with 1 micrometer CRF, urocortin, or urocortin II. The number of GABA-positive neurons in each treatment condition was counted at each culture age for monitoring the changes in neuronal survival. Treatment with 1 micrometer CRF or 1 micrometer urocortin increased the survival of GABAergic neurons at 6 days in vitro and 10 days in vitro, and this survival promoting effect was abolished by treatment with astressin in the presence of those peptides. Based on these data, we suggest that CRF or urocortin has a trophic role promoting the survival of cerebellar GABAergic neurons in cultures.
gamma-Aminobutyric Acid/*metabolism ; Time Factors ; Receptors, Corticotropin-Releasing Hormone/*metabolism ; Peptides/chemistry ; Neurons/*metabolism ; Mice, Inbred C57BL ; Mice ; Immunohistochemistry ; Image Processing, Computer-Assisted ; Corticotropin-Releasing Hormone/biosynthesis/*physiology ; Cerebellum/*embryology/*metabolism ; Cells, Cultured ; Cell Survival ; Animals

OBJECTIVETo explore the expression level of corticotropin-releasing hormone receptor type-1 (CRHR-1) in intrahepatic cholestatic placental (ICP) tissue.

METHODSHuman placental samples were collected from 10 ICP patients and 10 healthy controls after parturition at 37-40 weeks of gestation. CRHR-1 protein and mRNA expression was assessed by western blotting and nested-real-time fluorescence quantitative PCR, respectively. Normally distributed data were summarized as mean +/- standard deviation, and intergroup comparisons were made by two-tailed Student's t-test. Non-normally distributed data were presented as median with interquartile range, and intergroup comparisons were made by Wilcoxon test. For all statistical analyses, a two-tailed P-value of less than 0.05 was considered statistically significant.

RESULTSThe CRHR-1 fluorescence intensity was lower in ICP tissues (1.55 +/- 0.28) than in placental tissues from healthy controls (1.60 +/- 0.37), but the difference did not reach statistical significance (t = 0.349, P = 0.732). The CRHR-1 mRNA content was slightly higher in the ICP tissues [0.139(0.268)] than in the placental tissues from healthy controls [0.031(0.245)], but the difference did not reach statistical significance (t = 1.504, P = 0.136).

CONCLUSIONCRHR-1 expression is decreased in ICP tissues, which may lead to a smaller volume of placental lobular villi vessels and restrict the CRH positive feedback loop, ultimately promoting acute hypoxic stress and possible harm to the fetus.

Adult ; Case-Control Studies ; Cholestasis, Intrahepatic ; metabolism ; Female ; Humans ; Liver Cirrhosis, Biliary ; metabolism ; Placenta ; metabolism ; Pregnancy ; Pregnancy Complications ; metabolism ; Receptors, Corticotropin-Releasing Hormone ; metabolism

OBJECTIVETo study the changes in serum cortisol levels in adolescents with type 1 diabetes (T1DM) and elevated depressive symptoms.

METHODSTwenty-eight adolescents with T1DM and 31 healthy peers were assessed for depressive symptoms using a depression self-rating scale developed by the Epidemiological Survey Center. Selected subjects were classified into four groups: T1DM with elevated depressive symptoms group (n=15), T1DM without elevated depressive symptoms group (n=13), elevated depressive symptoms without T1DM group (n=15), and normal control group (n=16). Fasting blood samples were collected in the morning, and the levels of serum cortisol were compared among the four groups. The correlations of serum levels of cortisol and glycosylated hemoglobin A1c (HbA1c) with the score of depression self-rating scale were evaluated by Pearson correlation analysis.

RESULTSThe fasting serum cortisol levels in the 28 T1DM patients were significantly higher than in the 31 healthy peers (P<0.01). The fasting cortisol levels in the T1DM with elevated depressive symptoms group were significantly higher compared with those in the elevated depressive symptoms without T1DM group and normal control group (P<0.01). In adolescents with T1DM, serum HbA1c level was positively correlated with the score of depression self-rating scale (r=0.481, P=0.010).

CONCLUSIONSThe fasting serum cortisol levels in adolescents with T1DM and elevated depressive symptoms are significantly increased, suggesting that the patients with comorbidity of T1DM and depression develop dysfunction of the corticotropin-releasing hormone-adrenocorticotropic hormone-cortisol axis. The elevated depressive symptoms may be associated with a poor control of glucose metabolism.

Adolescent ; Adrenocorticotropic Hormone ; physiology ; Child ; Corticotropin-Releasing Hormone ; physiology ; Depression ; blood ; etiology ; Diabetes Mellitus, Type 1 ; blood ; Female ; Glucose ; metabolism ; Glycated Hemoglobin A ; analysis ; Humans ; Hydrocortisone ; blood ; Male