Neural Regulation of Corticotropin Releasing Hormone (CRH) and CRH Receptor mRNA in the Hypothalamic Paraventricular Nucleus in the Rat (original) (raw)

1996, Journal of Neuroendocrinology

The role of afferent innervation to the hypothalamic paraventricular nucleus (PVN) on CRH mRNA and CRH receptor mRNA levels was studied in control and stressed rats. Groups of rats were subjected to unilateral transection of the stria terminalis (ST), the medial forebrain bundle at the rostra1 hypothalamic level (RMFB), or the lower brainstem through the medulla oblongata between the obex and the locus coeruleus (CBs). Twelve days after surgery, each group of rats was further divided into controls (basal conditions) and stressed (1 h immobilization), before collecting brains for mRNA analysis by in situ hybridization histochemistry. While ST and RMFB cuts had no effect on basal CRH mRNA levels in the PVN, CBs cut decreased CRH mRNA in the PVN ipsilaterally to the knife cut but it was without effect on the contralateral side (-40% and -37% vs contralateral and sham-operated, respectively, P<O.Ol). Acute stress (rats were killed 3 h after immobilization) increased CRH mRNA levels by about 30% bilaterally, an effect which was unchanged by any of the three hemisections.