Biochemical and immunohistochemical evidence for the presence of motilin in pig cerebellum.

The presence of motilin in rat and porcine cerebellum was investigated by using high performance liquid chromatography (HPLC) coupled with radioimmunoassay or immunohistochemistry. The antibodies used for this study were raised against synthetic gastrointestinal porcine motilin, which is, so far, the only known sequence of this peptide. The results obtained show the presence of a sharp peak of motilin-like immunoreactivity after HPLC of porcine cerebellum extracts, with an elution time corresponding to that of synthetic porcine motilin. Motilin-like immunoreactivity was also detected immunohistochemically in porcine cerebellum. However no motilin-like immunoreactivity was detected in rat cerebellum biochemically or immunohistochemically. This finding suggests that if a motilin-like neuropeptide is present in rat cerebellum, its molecular form differs from that present in porcine cerebellum.