Generation of substance P carbamate in neutral aqueous solution. Relevance to inflammatory joint diseases.
High-field proton (1H) nuclear magnetic resonance (NMR) spectroscopy has been employed to evaluate the formation of substance P carbamate in aqueous solution. Equilibration of substance P with physiologically relevant concentrations of bicarbonate (2.50 x 10(-2) mol.dm-3) at pH 7.00 generated a new multiplet signal centred at 4.13 ppm in its NMR spectrum, characteristic of the alpha-proton of peptide carbamate species. High-field 1H NMR spectroscopy also demonstrated that the model dipeptide, Arg-Gly, formed a carbamate in neutral aqueous solutions containing 2.50 x 10(-2) mol.dm-3 HCO3-. The physiological significance of these results is discussed in view of the central roles of vasoactive neuropeptides in human joint diseases and the hypercapnic environment of the inflamed rheumatoid joint.
Davis
A J
AJ
Department of Chemistry, Queen Mary and Westfield College, University of London, UK.
Hawkes
G E
GE
Haycock
P R
PR
O'Brien
P
P
Kidd
B L
BL
Mapp
P I
PI
Naughton
D
D
Grootveld
M
M
D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D002219:Carbamates / Q000138:chemical synthesis* / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D011522:Protons; D012996:Solutions; D013373:Substance P / Q000737:chemistry* / Q000378:metabolism; D014867:Water
D002219:Carbamates; D011522:Protons; D012996:Solutions; D014867:Water; D013373:Substance P