Background:

Morphine-like substances exist in brain or the pituitary of various species. Beta-lipotropin (beta-LPH) was found to contain within its C-terminal sequence the primary structure of these peptides.

Identity between the sequence of isolated fragments and thecarboxy terminal portion of the corresponding beta-lipotropins hasalso been observed in human and in porcine pituitary and hypothalamic-neurohypophysis extracts.

参考文献:
1. Bradbury, A.F., Smyth, D.G. and Snell, C.R. (1976), Biochem. Biophys. Res. Commun. 6!J, 950-956.
2. Ling, N., Burgus, R. and Guillemin, R. (1976). Proc. Natl. Acad. Sci. USA., 73, 3942-3946.