The distribution of motilin-like peptides in rhesus monkey brain as determined by radioimmunoassay.

The distribution of motilin-like immunoreactivity (MLI) was determined by radioimmunoassay in the major regions of rhesus monkey brain. In agreement with previous studies, motilin concentration was higher in pituitary and pineal than brain. MLI was widely distributed in rhesus monkey brain and was particularly high in claustrum, inferior colliculus, and cerebellar floculus. Sephadex G50 chromatography of monkey cerebellar and cerebral cortical extracts revealed multiple forms of MLI. The presence of MLI in rhesus monkey brain confirms previous reports of localization of motilin-like peptides by immunocytochemistry in the human cerebellum and is suggestive of a possible role for MLI in the functioning of the human brain.