Augmented amylase release from rat parotid gland slices, in vitro

Using a continuous amylase assay the effect of a simultaneous stimulation of adrenergic and cholinergic receptors on amylase release by perfused rat parotid slices was investigated. Superimposing adrenergic stimulation (isoprenaline) on continual submaximal cholinergic stimulation (acetyl-beta-methylcholine) resulted in an augmented amylase release compared with the sum of the two separate effects. This could also be shown with continual adrenergic stimulation with cholinergic stimulation superimposed on this. Possible explanations of this effect are discussed with particular respect to the role of Ca++.