Concentrations of Epidermal Growth Factor, Nerve Growth Factor, and Submandibular Gland Renin in Male and Female Mouse Tissue and Fluids*

Abstract

The submandibular gland of the mouse contains a variety of hormone-like substances and enzymes, such as epidermal growth factor (EGF), nerve growth factor (NGF), and submandibular gland renin (SGR). Using specific RIAs for each of these proteins and a radioreceptor assay (RRA) for EGF, the present study was performed to examine the concentrations of these three proteins and the molecular size of EGF in the submandibular glands and biological fluids of normal male and female mice. Submandibular glands of male mice contained far more radioimmunoassayable EGF, NGF, and SGR than those of female mice (66-, 92-, and 30-fold, respectively). Male saliva also contained far higher concentrations of radioimmunoassayable EGF, NGF, and SGR than that of the female (38-, 56-, and 49- fold, respectively). Furthermore, the molar concentrations of these proteins appeared to be similar to one another in submandibular gland tissue and in saliva. In contrast, although high concentrations of radioimmunoassayable and radiorecep...