Essential fatty acid treatment--effects on nerve conduction, polyol pathway and axonal transport in streptozotocin diabetic rats
Tomlinson, D.R.; Robinson, J.P.; Compton, A.M.; Keen, P.
Diabetologia 32(9): 655-659
This study was designed to examine the effect of dietary supplementation with essential fatty acids (evening primrose oil - 5% weight:weight added to the diet) on acute neurophysiological and neurochemical defects in streptozotocin-diabetic rats. Diabetic rats, which were not given evening primrose oil, showed highly significant elevations of nerve sorbitol and fructose combined with a depletion of nerve myo-inositol. In those animals there was also a 40% reduction (p < 0.02) in the accumulation of axonally transported substance P-like immunoreactivity proximal to a 12 h sciatic nerve ligature together with reduced motor nerve conduction velocity (13% [p < 0.001] and 20% [p < 0.001] in two separate experiments). Treatment of other diabetic rats with evening primrose oil prevented completely the development of the motor nerve conduction velocity deficit without affecting sorbitol, fructose or myo-inositol levels or the deficit in axonal transport of substance P. In a second experiment, treatment of diabetic rats with evening primrose oil was associated with significant attenuation of the conduction velocity deficit, but not complete prevention.