Kallikrein concentration in submandibular glands of rats chronically treated with isoproterenol.

The effect of chronic beta-adrenergic stimulation with isoproterenol on the kallikrein content of rat submandibular gland was estimated by radioimmunoassay, by immunohistochemistry, and by analytical isoelectric focusing. Radioimmunoassays revealed that the kallikrein content of the submandibular gland was already significantly decreased after 6 days of treatment. After 21 days, the kallikrein content was 40 times lower and by 33 days an almost complete depletion was found. These findings were confirmed by immunohistochemistry. Analytical isoelectric focusing also showed that, after 33 days of treatment, the typical bands corresponding to the kallikrein isoenzymes of the submandibular gland had disappeared. These results indicate that kallikrein secretion is influenced by beta-adrenergic stimulation.