1. The cellular localization of kallikrein was investigated in rat and human exocrine glands and kidney by a direct immunofluorescence technique.
2. Kallikrein was found in the duct system of the rat and human major salivary glands.
3. Kallikrein was found in the distal tubular cells of the rat kidney. Attempts to localize kallikrein in the human kidney were unsuccessful.
4. In the rat and human pancreas, kallikrein was found as a pro-enzyme in the acinar cells.