Effects of lithium on inositol phospholipid hydrolysis and inhibition of dopamine D1 receptor-mediated cyclic AMP formation by carbachol in rat brain slices.
The in vitro and ex vivo effects of lithium on muscarinic cholinergic inositol phospholipid hydrolysis and muscarinic cholinergic inhibition of dopamine D1-receptor-stimulated cyclic AMP formation were examined in rat brain slices. Following chronic lithium feeding, carbachol-stimulated inositol phosphate accumulation was reduced ex vivo in slices of cerebral cortex but not in striatal slices. Lithium (1 mM) in vitro had no direct effect on dopamine D1-receptor-stimulated cyclic AMP formation, but enhanced the inhibitory effect of carbachol on the D1 response, in striatal slices, and this was not significantly altered by prior lithium feeding. Lithium therefore has effects on two discrete muscarinic responses in rat brain which are apparently maintained after chronic exposure to the ion and might be relevant to its antimanic actions.
Whitworth
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P
Department of Physiology and Pharmacology, University of Nottingham Medical School, Queen's Medical Centre, England.
Kendall
D A
DA
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D000242:Cyclic AMP / Q000096:biosynthesis*; D004298:Dopamine / Q000494:pharmacology; D006868:Hydrolysis; D066298:In Vitro Techniques; D008094:Lithium / Q000494:pharmacology*; D008297:Male; D010716:Phosphatidylinositols / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000502:physiology*; D017447:Receptors, Dopamine D1
D010716:Phosphatidylinositols; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D002217:Carbachol; D008094:Lithium; D000242:Cyclic AMP; D004298:Dopamine