Identification and characterization of parathyroid hormone/parathyroid hormone-related peptide receptor in cultured astrocytes.

Parathyroid hormone (PTH)/parathyroid hormone-related peptide (PTHrP) receptor expressed in rat cultured cortical type I astrocytes was identified and characterized. Northern blot analysis demonstrated that the PTH/PTHrP receptor mRNA is expressed in astrocytes. A human PTH fragment, PTH [1-34], stimulated adenylate cyclase with the EC50 value of 3 nM, but not phospholipase C. PTH [1-34] changed the morphology of protoplasmic type astrocytes into process-bearing ones. Thus, type I astrocytes possess PTH/PTHrP receptor that is coupled to an adenylate cyclase-activating system but not to phospholipase C.