<prompt> All regulation of renal potassium excretion total body potassium balance occurs inProximal convoluted tubuleAscending loop of HenleDescending loop of HenleCollecting duct  <response>: Changes in whole-body K content are primarily mediated by the kidney, which reabsorbs filtered K in hypokalemic, K-deficient states and secretes K in hyperkalemic, K-replete states. Although K is transpoed along the entire nephron, it is the principal cells of the connecting segment CNT and coical CD that play a dominant role in renal K secretion, whereas alpha-intercalated cells of the outer medullary CD function in renal tubular reabsorption of filtered K in K-deficient states. Ref: Harrison 19e pg: 304 