Heterogeneity of immunoreactive prolactin in the rat brain.
Three immunoreactive prolactin proteins (24 Kd, 16 Kd, and 12 Kd) were identified in the rat brain using sodium dodecyl sulphate polyacrylamide gel electrophoresis, and western blot analyses. In male and female brains, the primary prolactin protein has a molecular weight of 24 Kd which is similar to that of pituitary prolactin. Two additional proteins with apparent molecular weights of 16 Kd and 12 Kd were also identified and were found in greater concentrations in the brain than in the pituitary, and were more predominant in the female brain. In addition, brain extracts proteolytically modify the 24K dalton PRL resulting in the formation of two fragments with apparent molecular weights of 16 and 8 Kd. These data indicate that the prolactin identified in the rat brain is similar to pituitary prolactin, and suggests, that like other PRL target tissues the brain may have the capacity to proteolytically modify prolactin.
DeVito
W J
WJ
Division of Endocrinology, University of Massachusetts Medical Center, Worcester 01605.
D000818:Animals; D000906:Antibodies; D001923:Brain Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D008297:Male; D008970:Molecular Weight; D009928:Organ Specificity; D010902:Pituitary Gland / Q000032:analysis; D011388:Prolactin / Q000032:analysis* / Q000276:immunology; D051381:Rats; D011919:Rats, Inbred Strains; D012737:Sex Factors
D000906:Antibodies; D011388:Prolactin