Transport to the bloodstream of amylase following retrograde infusion of amylase into the parotid glands in the rat.

Amylase secretion into parotid saliva was increased more by isoprenaline whereas the secretion rate of parotid saliva was increased more by pilocarpine. Retrograde infusion of parotid-amylase solution into excretory ducts of the parotid gland elevated the activity of the enzyme in the serum. Direct evidence that retrogradely-infused amylase reaches the blood from the parotid gland was obtained using amylase prepared from Bacillus subtilis. Pretreatment with pilocarpine accelerated the release of amylase into the blood. The elevation of intraductal pressure may be the primary mechanism for the release of amylase into the blood from the parotid glands.