Histaminergic and noradrenergic control of cyclic AMP formation in the pineal gland and cerebral cortex of three avian species: cock, duck, and goose.

The goal of the present study was to examine the effects of forskolin (FOR), histamine (HA), L-noradrenaline (NA), isoprenaline (ISO) and dopamine (DA) on cyclic AMP formation in whole pineal glands and cerebral cortical slices of cock, duck and goose. HA (100 muM) and FOR (10 muM) potently increased cyclic AMP production in the pineal glands of all studied avian species, showing a synergistic interaction when applied together. HA at the dose of 1 mM significantly stimulated adenylyl cyclase activity in the membrane preparations of cock pineal glands while lower concentrations were ineffective. HA markedly enhanced cyclic AMP formation in cerebral cortex of cock (an effect being potentiated for FOR), but did not affect the nucleotide production in this brain structure of duck and goose. DA (100 muM) had no effect, NA (100 muM) only moderately (5-22% increased, where ISO (10muM) significantly (by 50-90%) enhanced cyclic AM_ synthesis in avian cerebral cortex. Propranolol (1 muM) antagonized all these effects, while preincubation with yohimbine and prazosin significantly enhanced NA action in cortical slices of duck and goose.