The aim of this study was to evaluate the radioprotective effect of vitamin E in salivary gland function, aswell as analyse the total protein concentration. For this purpose 90 mate rats were used and randomly divided into five experimental groups: control (I), in which animals received olive oil solution but were not irradiated; irradiated-otive oil (II), in which animals received olive oil solution and were irradiated with a single exposure dose of 15 Gy of gamma rays to the head and neck region; irradiated (III), in which animals were only irradiated with a single exposure dose of 15 Gy of gamma rays; vitamin E (IV), in which animals received alpha tocopherot acetate solution but were not irradiated; irradiated-vitamin E (V), in which animals received a tocopherot acetate solution before irradiation with a single exposure dose of 15 Gy gamma rays. The animals were sacrificed 4, 8 h and 30 days after the irradiation procedure. No differences were observed in salivary volumes between the groups at 4 and 8 h. At 30 days, the salivary volume in the animals pertaining to the irradiated-olive oil group was significantly reduced in relation to the control group. The only irradiated group (III) presented significantly diminished salivary volume. In the salivary composition, no significant differences were observed in the total protein content between the groups studied. It was concluded that radiation had no effect on the total protein content and that vitamin E protected the salivary function 30 days after irradiation. Thus, vitamin E can be considered as a potential radioprotective substance. (c) 2005 Published by Elsevier Ltd.51296101