부산대학교 도서관

Melamine is a nitrogen heterocyclic triazine compound whose acute toxicity was considered to be low in mammals. The combined ingestion of melamine and cyanuric acid was shown be responsible for the crystalluria, kidney stones and subsequent renal failure in animals. In the present study, we investigated in mice the potential effects of melamine on immunohistochemical expression of Bax/Bc1-2 protein in testis and the estrogen receptor-α (ER)/progesterone receptor (PR) mRNA in the ovary with or without cyanuric acid. Our results indicated that at the dose range used, exposure to melamine alone or combination with cyanuric acid promoted the expression of Bax protein, and suppressed the expression of Bcl-2 protein in testis of male mice in a dose-dependent manner. The relative expression of ER-α in ovary was significantly downregulated in the animals from the melamine high dose group (50 mg/kg), as well as in the mixture groups of melamine and cyanuric acid at low (each at 1 mg/kg), middle (each at 5 mg/kg) and high doses (each at 25 mg/kg). The changing pattern of PR mRNA in the animals treated with melamine alone or combination of melamine and cyanuric acid were similar to those of ER-α mRNA. Compared with control group, however, no significant difference was observed in relative expression of PR mRNA in co-administration group of melamine and cyanuric acid with low dose (each at 1 mg/kg, P > 0.05). These results from the present study may provide useful information for evaluating the melamine-related reproductive toxicity in mammals. [ABSTRACT FROM AUTHOR]