Human parathyroid hormone does not influence human erythropoiesis in vitro

Background. Although renal anaemia is associated with secondary hyperparathyroidism, the relationship of both conditions remains obscure. Previously it was reported that high levels of bovine parathyroid hormone (PTH) did not inhibit in vitro human erythropoiesis, but whether human PTH inhibits in vitro human erythropoiesis has not been determined. Method. To clarify the direct effects of human biologically active N-terminal (1-34) PTH and intact (1-84) PTH on human haematopoietic progenitor growth, we investigated colony assays of human erythropoiesis and granulomonopoiesis. Results. Neither N-terminal PTH (300 ng/ml) nor intact PTH (5000 pg/ml) inhibited haematopoietic progenitor growth. Conclusion. Our findings confirm that human PTH does not directly inhibit human erythropoiesis.