Epidermal Growth Factor: Effects of Androgens and Adrenergic Agents

Epidermal growth factor (EGF) is a polypeptide extracted from male mouse submaxillary glands which promotes epidermal growth and keratinization in the immature mouse. Androgens markedly increase submaxillary gland EGF content but have no apparent effect on basal plasma or urine EGF levels; they appear to stimulate synthesis and storage, but not release, of submaxillary gland EGF. EGF is released into plasma by α-adrenergic agents and by cervical sympathetic nerve stimulation, suggesting that its release is regulated by the sympathetic nervous system. If androgens have induced a sufficient concentration of EGF in the gland, plasma levels of EGF rise dramatically as submaxillary gland levels of EGF fall in response to α-adrenergic agents. The increase in plasma EGF in response to a-adrenergic stimulation is abolished by excision of the submaxillary glands, but basal plasma and urine levels are unchanged. This raises the possibility that EGF is secreted by other tissues as well. Immunoreactive EGF is also present in high concentrations in mouse milk, saliva and urine. (Endocrinology95: 776, 1974)