Apoptosis effect of cadmium chloride on guinea pig adrenocortical cells

Objective To investigate the role of 44/42 MAPK on the apoptosis of adrenocortical cells induced by cadmium chloride(CdCl2) in vitro.Methods The male guinea pigs' adrenocirtical cells were dispersed and primarily cultured for 24 hrs,and incubated with CdCl2 at doses of 0,12.5,25,50,100 or 200 μmol/L for 1 h.Then the phosphorylation level of P44/42 and the protein expression level of c-Fos were measured with SDS-PAGE and Western-Blot.The cells were incubated with the same doses of CdCl2 for 2 h,then cell apoptosis rate was detected with flow cytometry.The phosphorylation level of P44/42 and the protein expression level of c-Fos were detected after the cells were treated with 100 μmol/L CdCl2 for 0,15,30,60,90,120 minutes respectively after the treatment.The cell apoptosis was detected at 0,0.5,1,2,3 or 4 hours.Results The average percentage of apoptotic cells increased with dosage(0～200 μmol/L for 1 h,from 1.99% to 73.48%) or duration(100 μmol/L for 0～4 h,from 1.04% to 71.55%) of CdCl2.At dosage of 0～200 μmol/L,CdCl2 could remarkably increase the phosphorylation level of P44(from 100% to 418%),the phosphorylation level of P42(1.1 times to 2.3 times),and the expression level of c-Fos(1.6 times,2.2 times,2.4 times,3.3 times or 2.8 times).100 μmol/L CdCl2 could remarkably increase the phosphorylation level of P44(1.5 times to 6.3 times),the phosphorylation level of P42(1.1～2.1 times),and the expression level of c-Fos(from 2.6 times to 4.1 times) when the cells were cultured with CdCl2 for 0～2 hours.Conclusion CdCl2 could induce apoptosis of adrenocortical cells through the over-phosphorylated P44/42 and in turn the over-expression of c-Fos.