Bicarbonate transport along the loop of Henle: effects of adrenal steroids

Tubule microperfusion experiments indicate the stimulation of bicarbonate transport (J(HCO3)) in the loop of Henle (LOH) in proximal tubules of rats by adrenal steroid hormones such as glyco- and mineralocorticoids. Adrenalectomized rats exhibit in 40% reduction in J(HCO3) along LOH, as indicated by microcalorimetric studies and fluid resorption by (14C)insulin. Administration of dexamethasone alone or along with aldosterone enhances J(HCO3).