THE INFLUENCE OF L-ARGININE ON BIOMECHANICAL PARAMETERS OF NATIVE ANDNONENZYMATICALLY GLYCATED RAT TAIL TENDONS

Rat tail tendons from animals of an age range from 35 days to 900 days were glycated using different glucose concentrations. After nonenzyma tic glycation the biomechanical properties of tendons from young rats approached that of old tendons. In tendons from old animals the glucos e incorporation was significantly lower than in young rat tail tendons . Addition of L-arginine to the glucose solution reduced the incorpora tion of glucose especially in young rats. The concentration of early g lycation products and of advanced glycation end products were measured via affinity chromatography on boronic acid agarose and relative fluo rescence per collagen content, respectively, Both parameters were sign ificantly reduced by an addition of 10 mmol/l arginine. Biomechanical changes due to glycation were partially reversed. Incubation of rat ta il tendons in L-arginine in the absence of glucose caused a dose depen dent binding of the amino acid mainly to the proteoglycan matrix. High concentrations of L-arginine induced pronounced biomechanical alterat ions contrary to the action of glucose. The biomechanical effect of L- arginine is compared to the action of Na+ and Ca2+ and discussed on th e basis of a structural model of the proteoglycan matrix. Incubation o f already glycated rat tail tendons with L-arginine caused a reduction of the elastic stress component. This effect was diminished by increa sing the preincubation interval with glucose. The equilibrium values o f the elastic fraction were achieved after approximately five days inc ubation with the amino acid.