Effect of mineralocorticoids on collecting duct hydrogen ion secretion in the rabbit

The purpose of this study was to elucidate the mechanism whereby a potassium infusion led to an elevation in the urine minus blood (ohm-B) PCO2 difference in alkaline urine of the rabbit. Rabbits given 9alpha-fluorohydrocortisone 16 h prior to study had a significantly high olm-B PCO2 than control rabbits. However, the ohm-B PCO2 was increased further after potassium infusion. These results suggest that the increased collecting duct hydrogen ion secretion in the rabbit may in part have been induced by mineralocorticoids and in addition been influenced by increasing the potassium concentration.