Biochemical properties of epidermal growth factor in the mouse kidney.

Epidermal growth factor (EGF) concentration in the mouse kidney was exceedingly low when compared with the submandibular gland level. Gel filtration of kidney extract showed that kidney EGF had the same molecular weight as the submandibular gland peptide. The isoelectric point of kidney EGF was between pH 4.3 and 4.6. From reversed phase HPLC, two species of EGF, alpha-EGF and beta-EGF, were clearly detected in the kidney sample.