[The effect on apoptosis in anterior pituitary induced by cadmium chloride and its relations with caspase-9 pathway]

To study the effects of cadmium chloride in anterior pituitary and the relation between apoptosis and expression of procaspase-9 mRNA.

In vivo studies:40 SD male rats were randomly distributed into four groups which were administered with CdCl2 at different doses by gavage for 6 weeks;

the rats' anterior pituitary cells were primarily cultured for 120 hours, then treated with CdCl2 at the dose of 0, 1.56, 3.12, 6.25, 12.50, 25.00, 50.00, 100.00 micromol/L for 6 hours; The indices included: expression of procaspase-9 mRNA, detection of apoptosis with TUNEL assay.

The results showed the excretion of ACTH, LH seemed to be decreased dramatically and the apoptosis inclined to enhance remarkably, and further more, the expression of procaspase-9 mRNA appeared to be increased significantly as compared with those of the control. It was show that a dose-effect relationship between the CdCl2 dosing and indices above with the regression analysis and a linear correlation between the mean gray value of apoptosis cell and the relative gray value of procaspase-9 mRNA positive cell. The results indicated that damnification, for example, apoptosis could be caused by certain dose of CdCl2 in anterior pituitary cells with dose dependent manner. Caspase-9 might play a role in the occurrence of apoptosis.

It was suggested that cadmium could induce apoptosis of anterior pituitary both in vivo and in vitro in the manner of dose-dependent, and caspase-9 might play a role during above processes.