Gene expression in the forebrain of dexamethasone-treated pigs: effects onstress neuropeptides in the hypothalamus and hippocampus and glutamate receptor subunits in the hippocampus

Gene expression studies advance our understanding of the effects of stress and glucocorticoids on brain function and give a new direction to animal we lfare research. In this context, the presence of messenger RNAs (mRNAs) for corticotrophin releasing hormone (CRH) and vasopressin (vp) in the porcine hypothalamus has recently been documented. This study investigated the exp ression of CRH, vr and ionotropic glutamate receptor (iGluR) subunit mRNAS in the brains of pigs treated with the synthetic glucocorticoid dexamethaso ne (Dex 5 mg kg(-1) i.v.). In the hypothalamus, VP, but not CRH, mRNA was r educed 3 hours after Dex. In the hippocampus, expression of mRNAs for some iGluR subunits appeared to he differentially regulated 6 hours after Dex. I n addition, CRH message was detected in the hippocampus and significantly u pregulated in the CA1 region 3 hours after Dex. The relevance of these find ings to stress neurobiology of the growing, pig is discussed. (C) 2000 Harc ourt Publishers Ltd.