beta. -lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant. beta. -endorphin
..beta..-Lipotropin is the predominant opioid peptide of the human pituitary and rat pars distalis and is present in concentrations essentially equimolar with corticotropin. When freshly obtained nonfrozen rat anterior pituitaries were homogenized with 0.2 M HCl, approximately 98% of the immunoreactivity detected utilizing an antiserum that crossreacts equally with ..beta..-lipotropin and ..beta..-endorphin coeluted with /sup 125/I-labeled human ..beta..-lipotropin upon molecular sieve chromatography. The remainder of the activity eluted with synthetic human ..beta..-endorphin. Similar results were obtained for human pituitary. HCl homogenization of thawed tissue or homogenization of fresh tissue with acetic acid yielded substantially greater concentrations of ..beta..-endorphin and decreased concentrations of ..beta..-lipotropin. In human subjects, acute anterior pituitary stimulation using either insulin-induced hypoglycemia or vasopressin administration was associated with increased plasma ..beta..-lipotropin and corticotropin levels. At the time of peak concentrations, no significant levels of ..beta..-endorphin were detectable. These data indicate the lack of significant amounts of ..beta..-endorphin in human pituitary. Additionally, there appears to be no specific intrapituitary conversion of ..beta..-lipotropin to ..beta..-endorphin.
- Research Organization:
- Mount Sinai Medical Center, New York
- OSTI ID:
- 6688316
- Journal Information:
- Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 75:6
- Country of Publication:
- United States
- Language:
- English
Similar Records
Beta-lipotropin is the major component of the plasma opioid response to surgical stress in humans
Specific radioimmunoassay of human. beta. -endorphin in unextracted plasma
Related Subjects
ACTH
RADIOIMMUNOASSAY
PEPTIDES
PITUITARY GLAND
ANTIGEN-ANTIBODY REACTIONS
IMMUNE SERUMS
IODINE 125
LABELLED COMPOUNDS
MAN
RATS
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENDOCRINE GLANDS
GLANDS
HORMONES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PITUITARY HORMONES
PRIMATES
PROTEINS
RADIOASSAY
RADIOISOTOPES
RODENTS
TRACER TECHNIQUES
VERTEBRATES
550601* - Medicine- Unsealed Radionuclides in Diagnostics