Effects of ethanol on the stress-induced expression of NGFI-A mRNA in the rat brain.
We investigated expression of NGFI-A/zif268 mRNA, reliable marker for neuronal activation in response to stress in the brain of rats pretreated with ethanol. The rats were orally administrated with either 25% sucrose or 20% ethanol (20 ml of kg body weight) 10 min before the onset of the stress. The rats were exposed to immobilization stress for 20 min and quickly decapitated. The brains were extracted and immediately frozen. The level of NGFI-A mRNA was evaluated by in situ hybridization histochemistry. Prior ethanol administration attenuated the immobilization stress-induced upregulation of NGFI-A mRNA level in the neocortex and hippocampus. However, in the paraventricular hypothalamic nucleus, prior administration of ethanol did not affect the upregulation of this gene. These data suggest that ethanol abolishes the forebrain component of the stress response while it fails to attenuate the stress response on a region of the brain that regulates the autonomic nervous system and the hypothalamo-pituitary-adrenal axis. Regional differences in the expression of NGFI-A mRNA may be important for the complex interactions between ethanol and stress.
Ueyama
T
T
Department of Anatomy and Neurobiology, Wakayama Medical College, Japan. tueyama@wakayama-med.ac.jp
Ohya
H
H
Yoshimura
R
R
Senba
E
E
D000818:Animals; D002492:Central Nervous System Depressants / Q000097:blood / Q000494:pharmacology*; D004268:DNA-Binding Proteins / Q000187:drug effects* / Q000378:metabolism; D051766:Early Growth Response Protein 1; D000431:Ethanol / Q000097:blood / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D017874:Immediate-Early Proteins; D007103:Immobilization / Q000009:adverse effects; D008297:Male; D019579:Neocortex / Q000187:drug effects / Q000378:metabolism; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000378:metabolism*; D013395:Sucrose / Q000494:pharmacology; D014157:Transcription Factors / Q000187:drug effects* / Q000378:metabolism
D002492:Central Nervous System Depressants; D004268:DNA-Binding Proteins; D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D017874:Immediate-Early Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D000431:Ethanol; D013395:Sucrose