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

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 observe the role of corticotropin releasing factor receptor 2 antisense oligodeoxynucleotide (CRFR2ASO) of hypothalamus in hypermetabolism in rats with severe burn.

METHODSStainless-steel cannula were implanted into the 3rd ventricle. According to different medicine delivered into the 3rd ventricle, 30 SD rats with 30% TBSA full-thickness burn were divided randomly into burn control group (BC, with injection of 3 microL saline), CRFR1ODN group (with injection of CRFR1ODN 10 microg), CRFR1ASO group (with injection of CRFR1ASO 10 microg), CRFR2ODN group(with injection of CRFR2ODN 10 microg), CRFR2ASO group (with injection of CRFR2ASO 10 microg), with 6 rats in each group. Another 6 rats served as normal control (NC) and they received isotonic saline 3 microL instead. Different medicines were respectively delivered into respective group on 5, 6 post injury day (PID), then 3 microL gentian violet was introduced on 7 PID. Resting energy expenditure (REE) value and the expression level of hypothalamus CRFR2mRNA and CRFR2 protein were determined.

RESULTSREE value in BC, CRFR1ODN, CRFR1ASO, CRFR2ODN, CRFR2ASO groups was 11 840 +/- 987, 11 133 +/- 1100, 10 733 +/- 1338, 11 123 +/- 1321, 7563 +/- 890 kJx(m2)(-1)xd(-1), respectively, which were obviously higher than that in BC group [6641 +/- 526 kJx(m2)(-1)xd(-1), P < 0.05]. REE value in CRFR2ASO group was obviously lower than that in CRFR2ODN group (P < 0.01). The expression level of hypothalamus CRFR2 mRNA and its protein in BC group were increased after burn, which were obviously lower in CRFR2ASO group than NC group (P < 0.01).

CONCLUSIONCentral application of CRFR2ASO can downregulate the expression level of hypothalamus CRFR2 mRNA and its protein, and reduce hypermetabolism. Hypothalamus CRFR2 may mediate hypermetabolism in burn rats.

Animals ; Burns ; metabolism ; Hypothalamus ; metabolism ; Male ; Oligodeoxyribonucleotides, Antisense ; metabolism ; RNA, Messenger ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Corticotropin-Releasing Hormone ; genetics ; metabolism

OBJECTIVE: To observe the expression of corticotropin-releasing factor-1 receptor in hippocampus of rats model of salicylate induced tinnitus. METHOD: Twenty-four rats were randomly divided into three groups, eight for each group. For Group A and Group B, 10% salicylic sodium solution was intraperitoneal injected each day at the dose of 350 mg/kg for 21 days in Group A and 14 days in Group B. Group C received intraperitoneal injection with the same amount of saline solution each day for 14 days. ABR were tested 2 days before, and 2 hours after the first administration and after the last injection. Immunohistochemical test and Western Blot were utilized to detect the expression of CRF1R in hippocampus for each group. RESULT: ABR thresholds tested 2 days before the first administration of the 3 groups showed no statistically significant difference (P > 0.05). At the time point of 2 hours after the first injection, the ABR thresholds of Group A and Group B rose by 25.90 dB SPL and 25.03 dB SPL compared with that before the administration, respectively (P < 0. 01). After the last administration, the ABR thresholds of Group A and Group B rose 34.91 dB SPL and 32.62 dB SPI. compared with that before the administration, respectively (P < 0.01). The ABR thresholds of Group C showed no significant statistical difference at all the tested time points (P > 0.05). Immunohistochemical test and Western Blot revealed that the expression level of CRF1R in the hippocampus was A > B > C (P < 0.05). CONCLUSION The expression of CRF1R in the hippocampus of salicylate induced tinnitus rat increased with the injection time, illustrating that CRF1R may participate in the mechanism of tinnitus involving the limbic system.
Animals ; Auditory Threshold ; Disease Models, Animal ; Hippocampus ; metabolism ; Injections, Intraperitoneal ; Rats ; Receptors, Corticotropin-Releasing Hormone ; metabolism ; Salicylates ; adverse effects ; Tinnitus ; chemically induced ; metabolism

Animals ; Brain ; metabolism ; Dehydroepiandrosterone ; therapeutic use ; Depressive Disorder, Major ; drug therapy ; metabolism ; physiopathology ; Humans ; Metyrapone ; therapeutic use ; Mifepristone ; therapeutic use ; Psychotic Disorders ; drug therapy ; metabolism ; physiopathology ; Pyrimidines ; therapeutic use ; Receptors, Corticotropin-Releasing Hormone ; antagonists & inhibitors ; Receptors, Glucocorticoid ; antagonists & inhibitors ; metabolism

OBJECTIVETo observe the effect of hesperidin on behavior and hypothalamic-pituitary-adrenal (HPA) axis of ratmodel of chronic stress-induced depression.

METHODChronic unpredictable mild stress (CUMS) was used to establish the rat depression model. Sixty male SD rats were divided randomly into six groups: the normal group, the model group, the hesperidin (40, 80, 160 mg x kg(-1)) group and the positive fluoxetine (10 mg x kg(-1)) group. They were orally administered with drugs for three weeks. The sucrose preference test and the forced swimming test (FST) were assayed to detect animal behavior. The levels of corticosterone (CORT) in serum, mRNA of corticotropin release factor (CRF) in hypothalamus as well as protein expression of glucocorticoid receptor (GR) in paraventricular nucleus (PVN) were determined to clarify the anti-depression effect and mechanism of hesperidin.

RESULTCompared with the model group, rats in the hesperidin (40, 80, 160 mg x kg(-1)) treatment group showed significant increase in the sucrose consumption and decrease in the immobility time in FST to varying degrees. Meanwhile, the excessively high serum CORT and adrenal index of CUMS rats were reversed by treatment with hesperidin. In addition, hesperidin inhibited CRF mRNA expression in hypothalamus and up-regulated GR protein expression in PVN among CUMS rats.

CONCLUSIONHesperidin could effectively improve the behavior of CUMS rats and show the anti-depression effect. Its mechanisms may be related to the function of regulating HPA axis.

Administration, Oral ; Animals ; Behavior, Animal ; drug effects ; Corticosterone ; blood ; Corticotropin-Releasing Hormone ; genetics ; metabolism ; Depression ; drug therapy ; etiology ; Fluoxetine ; administration & dosage ; Gene Expression Regulation ; drug effects ; Hesperidin ; administration & dosage ; pharmacology ; Hypothalamo-Hypophyseal System ; drug effects ; physiopathology ; Hypothalamus ; metabolism ; Male ; Models, Animal ; Pituitary-Adrenal System ; drug effects ; physiopathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Glucocorticoid ; metabolism ; Stress, Psychological ; complications ; drug therapy ; Sucrose ; metabolism ; Swimming ; Up-Regulation