ABSTRACT
Collected at the first hours (0, 6, 12, 24, 48) and days (3 and 5) of piglets life bone marrow was cultured (in vitro) during 48 and 72 hours in order to assess the efficiency of development and ability of isolated marrow cells to form erythroid colonies (CFU-E-Colony Forming Unit) and also to examine the erythroidal sensitivity to Ep addition. It was found that bone marrow of new born piglets shows high ability to form erythroid colonies (CFU-E), but low sensitivity to Ep (erythropoietin). The limited efficiency to form immature erythroid colonies following 12h as well as matured ones after 24h, has been also shown. Observed changes could be caused by the limited erythroidal cells sensitivity to Ep.
Subject(s)
Animals, Newborn , Bone Marrow Cells , Bone Marrow/drug effects , Erythroid Precursor Cells/drug effects , Erythropoietin/pharmacology , Animals , Cells, Cultured , Erythroid Precursor Cells/physiology , Reference Values , SwineABSTRACT
The effect of albuterol, a potent beta2-adrenergic agonist, on kidney production of erythropoietin (Ep) was studied. Its effects on erythroid colony (CFU-E) formation in vitro in rabbit bone marrow cultures were also assessed. Albuterol produced a significant increase in plasma Ep levels in conscious rabbits following 7 h intravenous infusion (50 (microgram/kg)/min). This effect was blocked by pretreatment of the rabbits with butoxamine (5 mg/kg ip), a potent beta2-adrenergic blocker. Albuterol in doses of 10(-10) to 10(-8) M in combination with Ep was also found to produce a significant increase in the numbers of CFU-E in the plasma clot culture system of rabbit bone marrow. This effect was blocked completely by DL-propranolol (10(-8) M) and by butoxamine (10(-8) M). The data presented suggest that albuterol, a potent activator of beta2-adrenergic receptors, increases kidney production of Ep in vivo and also produces a direct effect in combination with Ep on the proliferation of the erythroid progenitor cell compartment.
