| Abstrakt: |
It was reported that the parathyroid gland hyperplasia correlated with enhanced co-expression of TGF-alpha and its receptor EGFR at early stages of renal failure. This time, we investigated the time course for EGFR and its ligands, TGF-alpha, and EFG expression, and the influence of high-phosphorus (P) diet to EGFR and EGF expression, and the effect of EGFR-tyrosine kinase inhibitor (Gefitinib, [IRESSA; AstraZeneca]; TKI) in rat PTGs with established stage of renal failure. The levels of EGFR, EGF, TGF-alpha mRNA in rat PTGs were increased for the time periods. The serum intact PTH levels, and EGFR, EGFmRNA in rat PTGs were suppressed in normal-P diet group. Nuclei positive cells for PCNA in TKI group were suppressed. The levels of p21mRNA were increased in TKI group. These results suggested that the enhanced expression of EGFR, TGF-alpha and EGF participate in the cell proliferation of hyperplastic PTGs in established stage of renal failure. |
