Bombesin, neurotensin and pro-gamma-melanotropin immunoreactants in human milk.
The concentration of bombesin-like, neurotensin-like and pro-gamma-melanotropin-like immunoreactants in human skim milk was measured by radioimmunoassay and found to be 235 pg/ml (mean, n = 13, range 60-430 pg/ml), 63 pg/ml (mean, n = 13, range 20-105 pg/ml) and 2.4 ng/ml (mean, n = 6, range 1.2-5 ng/ml), respectively. The concentrations were 5-10 times higher than in plasma. High performance liquid chromatography showed that the neurotensin and pro-gamma-melanotropin immunoreactants co-eluted with the authentic peptides. Bombesin gave three peaks, one co-eluting with authentic bombesin and one with porcine gastrin releasing peptide 14-27, whereas another one had a shorter elution time, suggesting a less hydrophobic fragment, possibly even smaller than gastrin releasing peptide 14-27.
D001839:Bombesin / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008895:Milk, Human / Q000032:analysis*; D009496:Neurotensin / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis*; D010455:Peptides / Q000032:analysis*; D011333:Pro-Opiomelanocortin / Q000032:analysis*; D011863:Radioimmunoassay
D010446:Peptide Fragments; D010455:Peptides; D009496:Neurotensin; D011333:Pro-Opiomelanocortin; D001839:Bombesin