PMID- 2026720
OWN - NLM
STAT- MEDLINE
DCOM- 19910610
LR  - 20190629
VI  - 562
IP  - 1-2
DP  - 1991 Jan 2
TI  - Analysis of methionine enkephalin in human pituitary by multi-dimensional 
      reversed-phase high-performance liquid chromatography, radioreceptor assay, 
      radioimmunoassay, fast atom bombardment mass spectrometry, and mass 
      spectrometry-mass spectrometry.
PG  - 573-84
AB  - Methionine enkephalin (ME = YGGFM) was measured in five individual human 
      post-mortem pituitaries using four different analytical methods, with the 
      objective of comparing the molecular specificities of the methods. Radioreceptor 
      assay (RRA) used a receptor-rich preparation from brain and [3H]etorphine as 
      radioligand to determine ME-like receptoractivity (ME-LR). Radioimmunoassay (RIA) 
      measured ME-like immunoreactivity (ME-LI). Pituitary samples analyzed by RRA and 
      RIA were purified first with a high-performance liquid chromatography (HPLC) 
      gradient on a polymer analytical column. Fast atom bombardment mass spectrometry 
      (FAB-MS) in two different detection modes quantified ME using the protonated 
      molecular ion MH+ of ME at 574 a.m.u. and B/E linked-field selected reaction 
      monitoring (SRM) to monitor the specific unimolecular metastable transition that 
      produced the unique amino acid sequence-determining tetrapeptide fragment ion 
      YGGFA+ from the MH+ precursor ion. Both FAB-MS methods used the deuterated 
      internal standard YGG[2H5-F]M. Samples analyzed with FAB-MS were purified first 
      with multi-dimensional reversed-phase HPLC. The first dimension was an ODS 
      gradient, and the second dimension was a polymer isocratic elution. The following 
      ME amounts were measured (mean +/- standard error of the mean): ME-LR, 7.0 +/- 
      1.9 micrograms g-1 tissue; ME-LI, 1.8 +/- 0.7 micrograms g-1 tissue; MH+, 2.7 +/- 
      0.6 micrograms g-1 tissue; SRM, 3.0 +/- 0.8 micrograms g-1 tissue. The FAB SRM 
      method provided the highest level of molecular specificity amount these four 
      analytical methods used to measure picomole amounts of endogenous ME in a human 
      pituitary.
FAU - Lovelace, J L
AU  - Lovelace JL
AD  - Department of Biochemistry, University of Tennessee, Memphis 38163.
FAU - Kusmierz, J J
AU  - Kusmierz JJ
FAU - Desiderio, D M
AU  - Desiderio DM
LA  - eng
GR  - GM26666/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - J Chromatogr
JT  - Journal of chromatography
JID - 0427043
RN  - 58569-55-4 (Enkephalin, Methionine)
SB  - IM
MH  - Adult
MH  - Animals
MH  - Chromatography, High Pressure Liquid
MH  - Dogs
MH  - Enkephalin, Methionine/*analysis
MH  - Humans
MH  - Limbic System/chemistry
MH  - Mass Spectrometry
MH  - Pituitary Gland/*chemistry
MH  - Radioimmunoassay
MH  - Radioligand Assay
MH  - Spectrometry, Mass, Fast Atom Bombardment
EDAT- 1991/01/02 00:00
MHDA- 1991/01/02 00:01
CRDT- 1991/01/02 00:00
PHST- 1991/01/02 00:00 [pubmed]
PHST- 1991/01/02 00:01 [medline]
PHST- 1991/01/02 00:00 [entrez]
AID - 10.1016/0378-4347(91)80609-g [doi]
PST - ppublish
SO  - J Chromatogr. 1991 Jan 2;562(1-2):573-84. doi: 10.1016/0378-4347(91)80609-g.