Dissociation of changes in hypothalamic corticotropin-releasing hormone and pituitary proopiomelanocortin mRNA levels after prolonged stress exposure.
Repeated immobilization stress for 7 days caused marked increase in corticotropin-releasing hormone (CRH) mRNA in the paraventricular nucleus (PVN, 90% above the control) and proopiomelanocortin (POMC) mRNA in the anterior pituitary (73% above the control) in rats. Prolongation of the stress exposure to 42 days led to a decline of CRH mRNA response (42% above the control) in comparison with that after 7 days, while POMC mRNA persisted at the same level. Observed adaptation of CRH but not POMC responses suggests that other factor(s) next to CRH participate in sustained rise in POMC expression during long-term stress.
D000222:Adaptation, Physiological; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000235:genetics*; D008297:Male; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism*; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D011333:Pro-Opiomelanocortin / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D013312:Stress, Physiological / Q000378:metabolism*; D013997:Time Factors