Collection and Quantitation of Mouse Salivary Secretions

Abstract

To investigate the effects of various drugs on mouse salivary glands, a method was developed for the direct quantitative collection of salivary secretions. Available methods for the collection of salivary secretions in various species are unsuitable for reproducible studies in mice (R. 0. WOLF and S. KAMEHASHI, J Dent Res 45:979, 1966; H. D. HALL and C. A. SCHNEYER, Proc Soc Exp Biol 115:100-105, 1964; D. E. DRUM, J Dent Res 42:892, 1963). Previous work performed on rat salivary preparations in this laboratory has led to the development of a collection technique that allows quantitative measurement of salivary secretions from either the parotid or submaxillary glands, in volumes as low as 0.5 p1. This technique also allows the direct application of various drugs to the salivary glands; the drugs can be administered either by constant infusion or by single injection into the systemic circulation. Consequently, drug interactions on mouse salivary glands can be studied by a quantitative approach using dose-response curves. Mice were anesthetized with sodium pentobarbital (5.0 mg/100 gm, intraperitoneally), and tracheotomies were performed. With a dissecting microscope (Bausch & Lomb), the parotid duct, and the brachial and femoral arteries were surgically exposed for cannulation (Illustration). The parotid duct was opened by puncturing the membrane of the duct with the tip of a 23 gauge needle; a polyethylene cannula (approximate dimensions: inside diameter (ID) 0.011 inches, outside diameter (OD) 0.024 inches to ID 0.003 inches, OD 0.006 inches) was inserted into the duct. The tight fit of the cannula in the duct eliminated the need for any securing procedure at the point of insertion; however, a femoral clamp was used to secure the system at a point approximately 0.25 inches from the free end of the cannula. A calibrated polyethylene collecting cannula (ID 0.030 inches, OD 0.048 inches) was placed over the free end of the parotid