ABSTRACT
Objective To investigate the signal regulatory mechanism of expression of corticotropin releasing hormone (CRH) stimulated neurons of hypothalamic slices in rats in vitro . Methods Model of hypothalamic slices of rats was established. After CRH stimulatation of corticotropin releasing hormone type 1 receptor (CRH1R) of hypothalamic slices in rats in vitro , the changes of activity of protein kinase A (PKA) signal passway were observed by immunocytochemical method and Western blotting. The relationship between the changes and CRH mRNA expression was also observed. Results CRH could cause the remarkable increase in phosphorylated PKA, phosphorylated CREB, and CRH content in hypothalamic slices in rats. However, CPl54526 or H89 could have significant inhibitory effect on the synthesis of P PKA, P CREB, and CRH. Conclusion PKA signal passway can regulate the ultrashort positive feedback of CRH secretion in the rat hypothalamus in stress due to severe trauma.