Neutral protease activity and erythropoietin production in the rat after cobalt administration.
The generation of erythropoietin purportedly involves the interaction of an enzyme, of renal origin, and a circulating plasma protein substrate. Cobalt, which has the capacity to stimulate erythropoietin formation, was evaluated for its effects on renal and plasma protease activity; in addition, the nature of the erythrogenic mechanism was investigated. Rats receiving one s.c. injection of cobalt demonstrated significant increases in activity of renal cathepsins A and B. The activity of a plasma protease was also elevated in rats after cobalt treatment. Cathepsins A and B and plasma protease were sensitive to the same enzymatic inhibitory agents, and all three enzymes demonstrated activity patterns similar to that of the renal erythropoietic factor [enzyme(s) presumed responsible for generating erythropoietin] in rats treated with cobalt. These data may help to elucidate the mechanism of erythropoiesis.
Neutral protease activity and erythropoietin production in the rat after cobalt administration. The generation of erythropoietin purportedly involves the interaction of an enzyme, of renal origin, and a circulating plasma protein substrate. Cobalt, which has the capacity to stimulate erythropoietin formation, was evaluated for its effects on renal and plasma protease activity; in addition, the nature of the erythrogenic mechanism was investigated. Rats receiving one s.c. injection of cobalt demonstrated significant increases in activity of renal cathepsins A and B. The activity of a plasma protease was also elevated in rats after cobalt treatment. Cathepsins A and B and plasma protease were sensitive to the same enzymatic inhibitory agents, and all three enzymes demonstrated activity patterns similar to that of the renal erythropoietic factor [enzyme(s) presumed responsible for generating erythropoietin] in rats treated with cobalt. These data may help to elucidate the mechanism of erythropoiesis.