Electrical responses of homing pigeon and guinea pig Purkinje cells to pineal indoleamines applied by microelectrophoresis

The effects of microelectrophoretically applied melatonin (aMT), 5-methoxytrytophol (ML), 5-hydroxytryptophol (HL) and noradrenaline (NA) on the electrical activity of cerebellar Purkinje and other cells during both day- and nighttime were studied in urethane-anesthetized intact and pinealectomized homing pigeons and guinea pigs. It is apparent from these studies that pineal indoleamines may play a modulatory role in the cerebellum.