TY - JOUR
T1 - Quantitation of the putative neurotransmitter agmatine as the hexafluoroacetylacetonate derivative by stable isotope dilution gas chromatography and negative-ion chemical ionization mass spectrometry
AU - Stickle, Douglas
AU - Bohrer, Alan
AU - Berger, Richard
AU - Morrissey, Jeremiah
AU - Klahr, Saulo
AU - Turk, John
N1 - Funding Information:
This work was supported by grants from the U. S. Public Health Service (NIH R37-DK-34388 and P41-RR-00954) and by the Washington University Diabetes Research and Training Center.
PY - 1996/7/1
Y1 - 1996/7/1
N2 - A method is described for detection and quantitation of agmatine [4- (aminobutyl)guanidine] by gas chromatography/negative-ion chemical ionization/mass spectrometry after derivatization with hexafluoroacetylacetone. The lower limit of detection of the derivative was about 25 fmol on-column. For quantitative studies of agmatine content in biological samples, a procedure utilizing an internal standard ([15N4]agmatine prepared from [15N4]arginine) and an extraction step had a lower limit of detection of about 15 pmol for total sample content. Agmatine content was measured in rat tissue samples and normalized to protein content. Kidney and spleen samples exhibited the greatest content of agmatine per unit protein mass but agmatine was also detected in pancreatic islets and brain regions (cerebellum and cerebral cortex). On the basis of these measurements, it is estimated that the pancreatic islet intracellular agmatine concentration may exceed 1 μM. The sensitive and highly specific means of detection and quantitation provided by mass spectrometry may be useful in investigating the physiological role of agmatine in mammalian systems.
AB - A method is described for detection and quantitation of agmatine [4- (aminobutyl)guanidine] by gas chromatography/negative-ion chemical ionization/mass spectrometry after derivatization with hexafluoroacetylacetone. The lower limit of detection of the derivative was about 25 fmol on-column. For quantitative studies of agmatine content in biological samples, a procedure utilizing an internal standard ([15N4]agmatine prepared from [15N4]arginine) and an extraction step had a lower limit of detection of about 15 pmol for total sample content. Agmatine content was measured in rat tissue samples and normalized to protein content. Kidney and spleen samples exhibited the greatest content of agmatine per unit protein mass but agmatine was also detected in pancreatic islets and brain regions (cerebellum and cerebral cortex). On the basis of these measurements, it is estimated that the pancreatic islet intracellular agmatine concentration may exceed 1 μM. The sensitive and highly specific means of detection and quantitation provided by mass spectrometry may be useful in investigating the physiological role of agmatine in mammalian systems.
UR - http://www.scopus.com/inward/record.url?scp=0030200688&partnerID=8YFLogxK
U2 - 10.1006/abio.1996.0265
DO - 10.1006/abio.1996.0265
M3 - Article
C2 - 8660601
AN - SCOPUS:0030200688
SN - 0003-2697
VL - 238
SP - 129
EP - 136
JO - Analytical Biochemistry
JF - Analytical Biochemistry
IS - 2
ER -