Furosemide treatment alters the distribution of kallikrein gene expression in kidneys of mice.

The renal kallikrein gene is normally expressed in convoluted distal and connecting tubules of the renal cortex. After furosemide treatment of mice there was strong expression also in the distal thick ascending limb of the loop of Henle in the renal outer medulla. This expansion of the kallikrein-expressing distal tubule cell population did not occur in mice on a sodium-restricted diet, in sodium-restricted mice given a high potassium diet or in untreated controls. Although the overall level of kallikrein gene expression was significantly greater in kidneys from furosemide-treated mice than in any other group, there was no detectable change in renal kallikrein gene expression in the submandibular glands after any of the treatments.