The effect of intracerebroventricularly administered dibutyryl adenosine 3′,5′-cyclic monophosphate on cerebrospinal fluid and serum dopamine-β-hydroxylase in rabbits

Intracerebrospinal injected or infused dibutyryl adenosine 3′,5′-cyclic monophosphate provoked (a) an initial small decrease of cerebrospinal fluid dopamine-β-hydroxylase activity which lasted for 2 hours, followed by a significant rise of a 4–6 hours duration, together with a rise in total cerebrospinal fluid protein concentration, (b) a significant increase in serum dopamine-β-hydroxylase activity. Pretreatment of rabbits with two intracisternal injections of 6-hydroxydopamine completely abolished the dibutyryl adenosine 3′,5′-cyclic monophosphate induced release of dopamine-β-hydroxylase in the cerebrospinal fluid but only partially the release of dopamine-β-hydroxylase in the serum.