HIGH-RESOLUTION PROTON NMR INVESTIGATIONS OF RAT-BLOOD PLASMA - ASSIGNMENT OF RESONANCES FOR THE MOLECULARLY MOBILE CARBOHYDRATE SIDE-CHAINS OF ACUTE-PHASE GLYCOPROTEINS

An intense broad resonance at 2.14 ppm present in high field (400, 500 and 600 MHz) Hahn spin-echo H-1-NMR spectra of rat blood plasma, but absent from those of human blood plasma is attributable to the presenc e of terminal 0-acetylsialate sugars in the molecularly mobile carbohy drate side-chains of 'acute-phase' glycoproteins (predominantly alpha1 -acid glycoprotein). The presence of such alternative acetylsugars in the carbohydrate side-chains of rat plasma glycoproteins are of much p hysiological and experimental significance in view of the regular use of these animals in model systems of human inflammatory conditions.