abnormal kidney collecting duct number increased kidney collecting duct number 2012-11-30T03:43:16Z MP:0011847 MPheno.ontology csmith larger than expected number of the kidney ducts that collect urine from the distal convoluted tubules, merge and become larger as they descend from the renal cortex into the medulla, and respond to vasopressin and aldosterone to regulate water, electrolyte and acid-base balance