<P> The outer segment of the medullary collecting duct follows the cortical collecting duct . It reaches the level of the renal medulla where the thin descending limb of loop of Henle borders with the thick ascending limb of loop of Henle </P> <P> The inner segment is the part of the collecting duct system between the outer segment and the papillary ducts . </P> <P> The terminal portions of the medullary collecting ducts are the "papillary ducts", which end at the renal papilla and empty into a minor calyx . </P> <P> Each component of the collecting duct system contains two cell types, intercalated cells and a segment - specific cell type: </P>

Where is the collecting duct in the kidney