The in vitro secretion of epidermal growth factor by mouse submandibular salivary gland

A technique for the study of epidermal growth factor (EGF) secretion from salivary gland pieces in vitro is described and the responses to a variety of drugs are compared to the results of previously reported in vivo studies. Adrenaline stimulates secretion of the growth factor as does the alpha-adrenergic agonist phenylephrine, while isoprenaline is less active in stimulating EGF secretion. Phentolamine, but not propranolol, blocks the secretory activity of adrenaline and isoprenaline in this system. Pretreatment of the salivary gland pieces with colchicine reduces the secretory response to adrenaline, suggesting an involvement of microtubular proteins in the process. It is anticipated that the in vitro technique described will provide a means by which detailed investigation of the secretion of epidermal growth factor can be made.