Effects of parathyroid hormone on the distribution and transport of calcium in cultured kidney cells.

The effects of parathyroid hormone (PTH) on the transport and distribution of calcium in isolated kidney cells were studied by kinetic analysis of 45Ca desaturation curves. The results show that PTH (15 ng/ml) increases the total cell calcium content, every exchangeable pool, and all exchange rates. The greatest effect is observed in the slowest kinetic phase which reflects a mitochondrial pool. The effects of PTH occur even in the absence of magnesium and of phosphate and the larger effect is again obtained in the mitochondrial pool. These results suggest that PTH stimulates calcium transport in kidney cells by affecting the intracellular distribution of calcium or by stimulating calcium influx.