Male Wistar rats were given unilateral postganglionic parasympathectomies by sectioning the auriculo-temporal nerve. 2. Analyses of the protein compositions of sympathetically induced saliva from both glands 1 week later revealed changes in the proportions of different secretory proteins, in particular amylase and basic proline-rich proteins were decreased. 3. These results suggest that parasympathetic impulses are required for the normal synthesis of amylase by parotid parenchyma in rats. Basic proline-rich proteins, known to require a sympathetic drive for normal synthesis, appear to require a parasympathetic input as well.