Effect of lithium on cyclic 3',5'-adenosine monophosphate formation in brain slices and its influence on phosphodiesterase.

The effect of lithium on cyclic 3',5'-adenosine monophosphate formation from precursor [8-14C]-adenine in guinea pig and rat brain slices and its influence on cAMP phosphodieesterase activity were studied. It was demonstrated that lithium stimulated cAMP formation in brain slices in correlation to its concentration. In guinea pig brain slices it stimulated cAMP formation in the presence of neurotransmitters and a phosphodiesterase inhibitor (histamine less than norepinephrine less than 5-OH-tryptamine). In rat brain slices, norepinephrine was also more effective than histamine. Phosphodiesterase inhibition was demonstrated only in preparations in which Triton X 100 was used.