ULCEROGENIC CINCHOPHEN INDUCES C-FOS EXPRESSION IN CRH-SECRETING CELLS IN THE PVH OF RAT-BRAIN

THIS study aimed at obtaining evidence that cinchophen, an ulcerogenic drug, stimulates the corticotropin-releasing hormone (CRH)-secreting cells in the paraventricular nucleus of the hypothalamus (PVH) to indu ce c-Fos expression. Without colchicine pretreatment, cinchophen was i njected i.p. 60 min before the time of maximum CRH level in the hypoth alamus, as decided by radioimmunoassay. Eighty percent of the c-Fos/CR H double-labelled cells were concentrated in the parvicellular subnucl ei. In the medial and anterior parvicellular subnuclei, the double-lab elled neurones of treated rats significantly outnumbered those of cont rols. The result shows that cinchophen induces excitation of the CRH-s ecreting cells.