Autonomic regulation of cystatin S gene expression in rat submandibular glands

Innervation of rat submandibular and parotid glands by the autonomic nervou s system regulates saliva volume, its rate of secretion and its composition . The autonomic nervous system also plays a regulatory role in the differen tiation and growth of salivary glands, and in the expression of specific se ts of genes. Rat cystatin S, a member of family 2 of the cysteine proteinas e inhibitor superfamily, is expressed in submandibular and parotid glands o f human and rat. In the rat, cystatin S gene expression is tissue- and cell type-specific, is temporally regulated during postnatal development, and n ot observed in adult animals. The beta-adrenergic agonist isoproterenol (IP R) induces hypertrophic and hyperplastic enlargements of rat salivary gland s and the expression of a number of genes including cystatin S. Sympathecto my reduces, but does not completely block, IPR-induced expression of the cy statin S gene in submandibular glands of adult female rats, indicating the participation of sympathetic factor(s) in its regulation. Bilateral parasym pathectomy also reduces IPR-induced cystatin S gene expression, suggesting a role of the parasympathetic nervous system in its regulation. Experiments described in this paper suggest that similar factor(s) arising from both t he sympathetic and parasympathetic branches of the autonomic nervous system simultaneously participate in IPR-induced cystatin S gene expression in su bmandibular glands. (C) 2000 Elsevier Science B.V. All rights reserved.