IMMUNOLOCALIZATION OF BRADYKININ B-2 RECEPTORS ON SKELETAL-MUSCLE CELLS

The kallikrein-kinin system has been implicated in the inflammatory pr ocess, blood pressure regulation, renal homeostasis, and glucose utili zation, The effects of Kallikrein and kinin on glucose uptake by the s keletal muscle are well established; however, the occurrence and the c ellular distribution of the kinin receptor(s) mediating these effects in the striated muscle are unknown, Using anti-peptide antibodies rais ed against the predicted intra- and extracellular domains of the B-2 r eceptor and the peroxidase/antiperoxidase system, we have been able to detect the B-2 receptor on the plasma membrane of striated skeletal m uscle cells of the rat hindlimb. A strong immunostaining appeared as a rim of immunoreactive material located on the periphery of striated m uscle cells. Cross-sectioned and longitudinally sectioned cells reveal ed a similar staining pattern, Alternatively, the immunostaining with specific antibodies to tissue kallikrein and to T-kininogen did not yi eld a significant staining of the striated muscle cells, Localization of the B-2 receptor on the surface of striated muscle cells provides a structural basis for the hypothesized physiological functions of the kinin system in the skeletal muscle.