Rat brain expresses serum calcium-decreasing factor (caldecrin).

We previously cloned the serum calcium-decreasing factor referred to as caldecrin from pancreas (J. Biol. Chem. 270 (1995) 30315). Caldecrin has been shown to be a chymotrypsin-type serine protease and to inhibit parathyroid hormone or parathyroid hormone-related peptide-induced bone resorption. In the present study, caldecrin was detected in adult rat brain by Western blotting and reverse transcription-polymerase chain reaction analysis. The caldecrin gene was constitutively expressed during postnatal days 1-28 in the brain. By in situ hybridization, the caldecrin mRNA was detected in the whole brain, including the olfactory bulb, cerebrum, hippocampus, thalamus, and cerebellum. These results suggest that caldecrin may play a role in the calcium homeostasis of the central nervous system.