Effect of argipressin and its related compounds on corticotropin releasing hormone contents in hypothalamus of rats

The paper mainly stresses on the effect of argipressin (Arg), 2-destyrosyl-3-desphenyl-alanyl-9-desglycyl-amide-Arg (Arg4-8), [1-deaminopenicillamine, 2-(o-methyl)tyrosine]-Arg (DPArg) and Arg antiserum on corticotropin releasing hormone (CRH) contents in median eminence (ME) and the level of plasma corticosterone after injected into the third ventricle of rats. The results show: 1) the CRH contents in ME significantly reduced with icv 100, 200, and 800 ng of Arg; 2) 100 ng of Arg4-8 and Arg antiserum (2 microliters, 1:1 diluted with 0.9% saline) increased CRH contents in ME and enhanced plasma corticosterone; 3) DPArg had no effect on CRH level but blocked the inhibitory role of Arg on central CRH. These results suggest that Arg acts as an inhibitory factor in regulating central CRH level and V1 receptor is involved.