May K+ ions stimulate the formation of cyclic AMP in the brain independently on their depolarizing action?

The effect of potassium ions on the formation of adenosine 3',5'-monophosphate (cAMP) in the rat cerebral cortex in vivo was studied under conditions where development of spreading depression had been blocked by pretreatment of the cerebral cortex by topically applied magnesium ions. A linear relationship between potassium concentrations applied to the cortical surface and levels of cAMP has been found. Moreover, potentiation of the K+-effect by magnesium ions has been observed.