THE GLOMERULAR PERIPOLAR CELL - AN IMMUNOHISTOCHEMICAL STUDY

The peripolar cell is a recently described glomerular epithelial cell which may be a new secretory component of the juxtaglomerular apparatu s (JGA). The purposes of this study were to identify immunohistochemic al markers specific for peripolar cells and to elucidate the compositi on of their cytoplasmic granules. We examined tissue from normal human and sheep kidneys with a variety of monoclonal antibodies and antiser a. A minority of peripolar cells showed immunoreactivity for vimentin but no other intermediate filament. Neuroendocrine markers were negati ve. The granules of peripolar cells contain a variety of plasma protei ns with the exception of IgM. It is likely that peripolar cells absorb plasma proteins from the glomerular filtrate. The reason for this is uncertain; however, their unique position at the vascular pole of norm al kidneys suggests a specialized function.