CHARACTERIZATION OF PHOSPHOINOSITIDE HYDROLYSIS PRODUCTS INDUCED BY HEXACHLOROCYCLOHEXANE ISOMERS IN RAT-BRAIN CORTEX

Water-soluble inositol metabolites were separated by anion-exchange ch romatography in order to determine whether or not gamma-hexachlorocycl ohexane (gamma-HCH, lindane) and related compounds affect phosphatidyl inositol hydrolysis in rat brain cortex slices. Hydrolysis was increas ed by delta- and gamma-HCH, while alpha- and beta-HCH were inactive. M uscarinic receptor stimulation of rat cortical slices with carbachol i ncreases inositol phosphates formation. The combined effect of carbach ol and the hexachlorocyclohexane isomers together were approximately e qual to the sum of the effect of each one separately. The results sugg est that lindane stimulates phosphoinositide phospholipase C and/or in hibits the phosphatases implicated in dephosphorylation of inositol ph osphates.