Immunohistochemical localization of kininogen in rat spinal cord and brain

Kininogen localization has been determined by immunocytochemistry in rat sp inal cord and brain using a kinin-directed kininogen monoclonal antibody. I n the spinal cord, there were immunostained neurons and fibers in laminae I , II, VII, and IX, intensely stained fibers in the superficial layers of th e dorsal horn, and immunoreactive glial and endothelial cells. Small neuron s, satellite cells, and Schwann cells immunostained distinctly in the dorsa l root ganglion. In the brain stem, there were immunoreactive neurons and f ibers in the tractus solitarius and nucleus, trigeminal spinal tract and nu clei, periaqueductal gray matter, vestibular nuclei, cochlear nuclei, trape zoid body, medial geniculate nucleus, and red nucleus. Immunostained neuron s and fibers were also found in cerebellum (dentate nucleus), cerebral cort ex (layers III and V), hippocampus (pyramidal cell layer), and corpus callo sum. Glia and endothelial cells stained in all brain regions. The widesprea d location of kininogen in neurons and their processes, as well as in glial and endothelial cells, indicates more than one functional role, including those proposed as a mediator, a calpain inhibitor, and a kinin precursor, i n a variety of neural activities and responses. (C) 1999 Academic Press.