Abstract: AIM: To study the effects of L-arginine on sebaceous gland hyperplasia in rats.METHODS: 10 mg·kg^-1 ·d^-11 of L-arginine was poured into the stomach in Sprague-Dawley rats for 7-14 d. The pathology phenomenon was observed in the rat skin.RESULTS: The backside skin of the male SD rats showed dewiness, greasiness and engrained yellow. The incidence was 100 % for 7 d in the male SD rats, 80 %in the female SD rats for 14 d, but 100 % in the immature female SD rats for 14 d.CONCLUSION: L-arg nine can facilitate the hyperplasia of sebaceous gland in SD rats.

Key words: L-arginine, nitric oxide, sebaceous gland, hyperplasia, rats