Detection of substance P in the central nervous system by a monoclonal antibody.

Abstract
Peptides with transmitter-like characteristics are being found in many brain areas. The application of immunocytochemical and radioimmunoassay methods has contributed much to the clarification of these neuronal systems. The development of a rat monoclonal antibody produced by a hybrid myeloma and its application to the study of 1 of these peptides, substance P was discussed. The hybrid clone, isolated after fusion of mouse myeloma cells with hyperimmune rat spleen cells, was obtained by a standardized and permanent source of monoclonal substance P antibodies in a culture cell system. This antibody recognizes the COOH-terminal part of substance P in radioimmunoassay down to 10-20 f[femto]mol. It does not crossreact with other known mammalian brain peptides tested. By immunofluorescence the antibody binds specifically and with a remarkably low background to nerve terminals and cell bodies located in clearly defined nuclear organizations of the CNS.