[pcDNA3.1 parathyroid hormone gene therapy of hypoparathyroidism: an experimental study].

OBJECTIVE

To investigate the effect of pcDNA3.1 parathyroid hormone (PTH) gene therapy for hypoparathyroidism and the best dosage.

METHODS

The parathyroid glands of 40 rabbits were resected so as to establish an animal model of hypoparathyroidism. The rabbits were randomly divided into 5 groups of 8 animals. Different doses of pcDNA3.1.PTH (50 micro g/kg, 150 micro g/kg, and 250 micro g/kg) containing human PTH gene, normal saline, and the vacant vector pcDNA3.1 were injected into the muscle of different groups of rabbits: Before parathyroidectomy and 1, 2, 3, 5, 7, 10, 15, 30, and 60 days after the operation blood was drawn to detect the concentrations of calcium and PTH.

RESULTS

The serum calcium and PTH began to increase one day after the injection of pcDNA3.1.PTH, and reached the peak concentrations at the seventh day. The levels lasted for two months. Seven days after the serum calcium and PTH were 2.83 +/- 0.02 mmol/L and 11.303 +/- 0.025 pg/ml respectively in 150 micro g/kg group and were 2.81 +/- 0.07 mmol/L and 12.001 +/- 0.008 pg/ml respectively in 250 micro g/kg group.

CONCLUSION

Human PTH gene therapy is effective in treating HPT with the most effective dose of 150 micro g/kg and 250 micro g/kg.