Secondary hyperparathyroidism in rats with experimentally induced pyelonephritis.

Abstract

The influence of induced pyelonephritis without uraemia on the function and morphology of the parathyroids was studied in the rat. Animals with induced pyelonephritis of the left kidney and simultaneous right nephrectomy were compared with animals with induced pyelonephritis of the left kidney and the right kidney left intact. Untreated animals served as controls. — The kidney function was evaluated by the serum creatinine and the polyethylene glycol clearance (GFR). Eight weeks after induction of pyelonephritis no obvious impairment of the total kidney function was observed in the pyelonephritis group without nephrectomy and only moderate impairment was found in the nephrectomized group. In both groups quantitative estimations showed that the induced pyelonephritis was accompanied by parathyroid hypertrophy and hyperplasia. Ultrastructural studies indicated a similar degree of enhancement of the parathyroid activity in the two experimental groups. The more pronounced renal dysfunction in the group with the right kidney removed was not accompanied by a higher degree of hypertrophy and hyperplasia of the parathyroids. — Our findings support the concept that in man also secondary hyperparathyroidism may develop in the presence of only slight or moderate impairment of the renal function.