Epidermal growth factor EGF in human saliva: effect of age, sex, race, pregnancy and sialogogue.

Saliva samples were obtained from volunteers either by spontaneous expectoration or after stimulation with citric acid (5%) and EGF was measured by a homologous radioimmunoassay. The mean +/- SEM of salivary human epidermal growth factor (hEGF) concentration in 70 males (aged 19-41) was 368.71 +/- 28.55 pmol/1 and 417.67 +/- 37.61 pmol/1 in 55 females (aged 19-45), P0.5. Values were found undetectable (32 pmol/1 in 6 prepubertal children. There was a tendency for hEGF to rise with age from about middle age but no significant racial or pregnancy related changes were observed. Stimulated sallivation with citric acid caused a fall in hEGF through a dilution effect. These results show that age has an important influence on the hEGF concentration of resting saliva.