The regional and subcellular distribution of immunoreactive α-melanocyte stimulating hormone (α-MSH1) in the post mortem adult human brain was investigated. α-MSHi was highly concentrated in medial basal hypothalamic tissue (1.02 ng/mg protein). Lower levels of α-MSHi were present in the optic chiasm and mammillary bodies, 0.08 and 0.11 ng/mg protein, respectively. The concentrations of α-MSHi in cerebellum and frontal cerebral cortex were 1/1,000th that of the medial basal hypothalamus. When medial basal hypothalamic homogenates were subjected to discontinuous or continuous sucrose density gradients, α-MSHi was found to be associated primarily with subcellular particles which resembled isolated nerve terminals, i.e., synaptosomes. Low to undetectable amounts of α-MSHi were found in the cytosol or the myelin/microsome fraction of the gradients. The results of these studies are consistent with the view that α-MSH is a neuronal peptide in the human brain.
- Human brain
- Neuronal peptide
- Subcellular fractionation
- α-Melanocyte stimulating hormone
ASJC Scopus subject areas