Controllability and duration of stress alter central nervous system depressant-induced sleep time in rats.
Rats were exposed to either 80 escapable shocks or yoked inescapable shocks and then injected with several hypnotic doses of sodium pentobarbital, midazolam, or ethanol; their sleep-time duration was compared with that of naive controls. Inescapable shock exposure resulted in a significant increase in ethanol-induced sleep time compared with the escapable shock and naive control groups. Both escape and yoked groups showed an increase in barbiturate-induced sleep time compared with controls, although no difference was observed for midazolam. Acute stress (twenty 5-s inescapable shocks) did not alter the depressant-induced sleep time for any of the drugs tested. These results illustrate the importance of psychological aspects of stress and its influence on the potency of certain depressants.
Drugan
R C
RC
Schrier Research Laboratory, Brown University, Providence, Rhode Island 02912.
Scher
D M
DM
Sarabanchong
V
V
Guglielmi
A
A
Meng
I
I
Chang
J
J
Bloom
K
K
Sylvia
S
S
Holmes
P
P
D000818:Animals; D001143:Arousal / Q000187:drug effects*; D001921:Brain / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004924:Escape Reaction / Q000187:drug effects*; D000431:Ethanol / Q000494:pharmacology*; D006380:Helplessness, Learned; D008297:Male; D008874:Midazolam / Q000494:pharmacology*; D010424:Pentobarbital / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time / Q000187:drug effects; D011963:Receptors, GABA-A / Q000187:drug effects*; D012894:Sleep Stages / Q000187:drug effects*
D011963:Receptors, GABA-A; D000431:Ethanol; D010424:Pentobarbital; D008874:Midazolam