Table 2.

Effects of valproate and lithium on [³H]inositol phosphates in carbachol-stimulated mouse cerebral cortical slices

Inositol phosphates	Carbachol	Valproate + carbachol	Lithium + carbachol
Monophosphates	53,000  ± 1,320	50,700  ± 917	128,400  ± 4,300
Ins(1,3)P2	495  ± 13	455  ± 34	1,340  ± 46
Ins(1,4)P2	10,700  ± 132	11,800  ± 132	85,200  ± 2,480
Ins(1,3,4)P3	201  ± 19	234  ± 10	402  ± 18

Values represent ³H disintegrations per minute in inositol phosphates. Prelabeled mouse brain cortical slices were preincubated for 12 min with or without sodium valproate (2 mM) or LiCl (10 mM) in KHBS (1.2 mM in CaCl₂). The reaction was continued for 12 min with carbamylcholine chloride (1 mM), then quenched with perchloric acid. The [³H]inositol phosphates in the neutralized extract were separated by HPLC. In each of three experiments, brains from six mice were used, and 0.4 mM myo-[³H]inositol was present during prelabeling. See Experimental Procedures for detailed methods.