The effects of melatonin therapy on hypothalamic-pituitary-adrenal axis in rats with posttraumatic stress disorder / 神经解剖学杂志

Objective:To investigate the effects of melatonin(MLT)on hypothalamic-pituitary-adrenal(HPA)axis in posttraumatic stress disorder(PTSD)rats induced by foot shocks.Methods:The rat model of PTSD was prepared by plantar electroshock,and MLT was given by intraperitoneal injection.The behavioral changes of rats were detected by rejection reaction test,the mRNA expression of corticotropin-releasing hormone(CRH)in hypothalamus was detected by real time RT-PCR,and the contents of adrenocorticotropin hormone(ACTH),epinephrine(EPI)and glucocorticoid(GC)in serum were detected by enzyme-linked immunosorbent assay(ELISA).Results:In the PTSD group,the rejection reaction was obvious,the expression of CRH mRNA in hypothalamus was increased(P＜0.05),the serum ACTH and EPI were increased(P＜0.05),but the GC level was decreased(P＜0.05).After MLT treatment,the rejection reaction of PTSD rats was significantly alleviated,CRH mRNA expression in hypothalamus was decreased(P＜0.05),serum ACTH and EPI levels were decreased(P＜0.05),and GC levels were increased(P＜0.05).Conclusion:MLT treatment can relieve the symptoms of PTSD and restore the neuroendocrine balance of HPA axis in rats.

Inhibition of Cell Migration by Corticotropin-Releasing Hormone (CRH) in Human Natural Killer Cell Line, NK-92MI

BACKGROUND: Natural killer (NK) cells are CD3 (-) CD14 (-) CD56 (+) lymphocytes. They play an important role in the body's innate immune response. They can induce spontaneous killing of cancer cells or virus-infected cells via the Fas/Fas ligand or the granzyme/perforin systems. The corticotropin-releasing hormone (CRH) is an important regulator for the body's stress response. It promotes proliferation and migration of various cancer cells through the CRH type 1 receptor under stress, and also inhibits NK or T cell activity. However, the relationship of CRH and NK cell migration to the target has not been confirmed. Herein, we study the effect of CRH on NK cell migration. METHODS: We used the human NK cell line, NK-92MI, and tested the expression of CRH receptor type 1 on NK-92MI by RT-PCR. This was to examine the effect of CRH on tumor and NK cell migration, thus NK cells (NK-92MI) were incubated with or without CRH and then each CRH treated cell's migration ability compared to that of the CRH untreated group. RESULTS: We confirmed that CRH receptor type 1 is expressed in NK-92MI. CRH can decrease NK cell migration in a time-/dose-dependent manner. CONCLUSION: These data suggest CRH can inhibit NK cell migration to target cells.

Enhancement of Cell Migration by Corticotropin-Releasing Hormone (CRH) in Human Gastric Cancer Cell Line, MKN-28

BACKGROUND: Corticotropin-Releasing Hormone (CRH), an important regulator of stress response, has a potent immunoregulatory effect with the ability to promote the growth of various cancer through CRH receptor type 1 under stress. Although the metastasized cancers through cell migration are more aggressive than the primary cancers, little is known about the effect of CRH on cell migration. Gastric cancer is prone to metastasize to other tissues and it is reported that gastric cancer is response to various stresses such as oxidative stress. Herein, we studied the relationship between CRH and gastric cancer cell migration. METHODS: We used gastric cancer cell line, MKN-28 and tested the CRH receptor type 1 expression on MKN-28 by RT-PCR. To examine the change in the ability of migration by CRH in MKN-28, cells were incubated with CRH and then migration ability was measured using a cell migration assay. RESULTS: We confirmed that CRH receptor type 1 was expressed in MKN-28 and HaCaT cells. The migration ability of MKN-28 cells was increased by CRH in a time-, dose- dependent manner. CONCLUSION: These data suggest that CRH increases migration ability in gastric cancer cell line and that CRH may be a critical regulator in the metastasis of gastric cancer cell.