Lithium affects REM sleep occurrence, autonomic activity and brain second messengers in the rat.
The effects of a single intraperitoneal administration of lithium, a drug used to prevent the recurrence of mania in bipolar disorders, were determined in the rat by studying changes in: (i) the wake-sleep cycle; (ii) autonomic parameters (hypothalamic and tail temperature, heart rate); (iii) the capacity to accumulate cAMP and IP(3) in the preoptic-anterior hypothalamic region (PO-AH) and in the cerebral cortex (CC) under an hypoxic stimulation at normal laboratory and at low ambient temperature (T(a)). In the immediate hours following the injection, lithium induced: (i) a significant reduction in REM sleep; (ii) a non-significant reduction in the delta power density of the EEG in NREM sleep; (iii) a significant decrease in the concentration of cAMP in PO-AH at normal laboratory T(a); (iv) a significant increase of IP(3) concentration in CC following exposure to low T(a). The earliest and most sensitive effects of lithium appear to be those concerning sleep. These changes are concomitant with biochemical effects that, in spite of a systemic administration of the substance, may be differentiated according to the second messenger involved, the brain region and the ambient condition.
Jones
Christine Ann
CA
Dipartimento di Fisiologia umana e generale, Università di Bologna, Bologna, Italy. christineann.jones@unibo.it
Perez
Emanuele
E
Amici
Roberto
R
Luppi
Marco
M
Baracchi
Francesca
F
Cerri
Matteo
M
Dentico
Daniela
D
Zamboni
Giovanni
G
D000704:Analysis of Variance; D000818:Animals; D018692:Antimanic Agents / Q000494:pharmacology*; D001341:Autonomic Nervous System / Q000187:drug effects; D001833:Body Temperature Regulation / Q000187:drug effects*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism; D004569:Electroencephalography / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007031:Hypothalamus / Q000187:drug effects; D000860:Hypoxia; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D018021:Lithium Chloride / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015290:Second Messenger Systems / Q000187:drug effects*; D012895:Sleep, REM / Q000187:drug effects*; D018709:Statistics, Nonparametric
D018692:Antimanic Agents; D015544:Inositol 1,4,5-Trisphosphate; D000242:Cyclic AMP; D018021:Lithium Chloride