敌枯双及其代谢产物对人胚上腭间质细胞生长的抑制作用

<正> 敌枯双[N,N′-methylene-bis-(2-amino-1,3,4-thiadiazole),MATDA]及其代谢产物敌枯唑(amino-1,3,4 thiadiazole,ATDA)对实验动物有致畸作用,前者作用明显大干后者,但至今仍未发现人群食用喷药后稻米有致畸作用,推测可能由于:人对敌枯双致畸作用不敏感,接触水平低和人体内烟酰胺的拮抗作用(已证实烟酰胺可拮抗敌枯

Inhibitory effects of N, N''''-methylene-bis-(2-amino-l, 3,4-thiadiazole) and its metabolite on growth of humanembryonic palatal mesenchyme cells

N, N/-methylene-bis-(2-amino-l, 3, 4-thiadiazole) (MATDA) and ATDA which is a main metabolite of MATDA in the body were used to detect their inhibitory effects on the growth of the HEPM cells. The results showed that both of two chemicals inhibited the growth of the human embryonic palatal mesenchyme (HEPM) cells with a clear relation of dose-effect response. The IC50 (concentration that inhibits growth by 50%) of MATDA and ATDA were 1.32 μmol·L-1 and 0.197 mmol ·L-1,respectively. According to IC50 < 1 mmol·L-1 as a demarcation of teratogenesis MATDA and ATDA might be considered to have human teratogenic potential, which was also dependent on the dose and antagonistic action of nicotinamide.