Differential expression of fos family and jun family mRNAs in the rat hypothalamo-pituitary-adrenal axis after immobilization stress.
We aimed to clarify the regulatory mechanism of the hypothalamo-pituitary-adrenal axis that plays key roles in initiating stress responses, as well as the roles of immediate early genes in this process. We investigated the stress-induced activation of fos and jun family proto-oncogenes by means of in situ hybridization histochemistry. Immobilization stress induced c-fos and jun B mRNAs in the parvocellular region of the hypothalamic paraventricular nucleus, the anterior and intermediate lobes of pituitary, and in the adrenal gland after 7 min of immobilization, although no c-fos or jun B mRNAs were detected in these and other organs in control rats. The levels of these mRNAs peaked after 30-60 min of immobilization, then declined. A low level of fos B mRNA appeared at 15-30 min and peaked after 60-90 min. On the contrary, c-jun and jun D mRNAs were constitutively expressed in the paraventricular nucleus and adrenal cortex. These findings indicate that the members of the fos and jun family proto-oncogenes play different roles in the transcriptional regulation of genes involved in the hypothalamo-pituitary-adrenal axis, and that monitoring immediate early genes is a useful method for following stress-induced cellular responses in the neuro-endocrine system.
Department of Anatomy and Neurobiology, Wakayama Medical College, Japan.
E
E
Senba
S
S
Umemoto
Y
Y
Kawai
K
K
Noguchi
D000818:Animals; D015870:Gene Expression; D016762:Genes, fos; D016758:Genes, jun; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D017403:In Situ Hybridization; D008297:Male; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism; D010903:Pituitary Gland, Anterior / Q000378:metabolism; D010913:Pituitary-Adrenal System / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis; D016755:Proto-Oncogene Proteins c-jun / Q000096:biosynthesis; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000378:metabolism*; D013997:Time Factors; D014158:Transcription, Genetic
D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D012333:RNA, Messenger