Localization of kallikrein in rat pineal glands.

The presence of kallikrein mRNA has been reported in the pineal gland of rats. Using an antibody to rat tissue kallikrein, we immunohistochemically examined the localization of cell components producing tissue kallikrein in this gland. The kallikrein immunoreactive cells were scattered in the parenchyma of the pineal gland. Their cell bodies were polymorphic with cell processes and a large nucleus similar to that of the pinealocyte. Frequently immunoreactive materials were seen to be localized in the perivascular areas.