NERVE GROWTH-FACTOR ADMINISTRATION PROTECTS AGAINST EXPERIMENTAL DIABETIC SENSORY NEUROPATHY

Small fiber sensory neuropathy is one of the most common complications of diabetes mellitus. Currently there is no adequate therapy to preve nt this often debilitating problem. Nerve growth factor (NGF) is a pro tein that promotes the survival and integrity of a large percentage of sensory neurons including the small fiber pain transmitting neurons w hich are often prominently affected in diabetic neuropathy. We report here that exogenously administered NGF is capable of preventing the be havioral and biochemical manifestations of diabetic sensory neuropathy in a streptozocin induced rat model. NGF administration prevented the elevation of tailflick threshold (a measure of the rat's response to a thermal noxious stimulus) which occurred in streptozocin-induced dia betic rats. Further, it prevented the induced reduction in levels of t he neuropeptides substance P and calcitonin gene related peptide measu red from cervical dorsal root ganglia. Finally, NGF did not ameliorate the prolonged latency of the compound action potentials measured from the caudal nerve of the tail. In view of these results, a clinical tr ial of NGF in diabetic neuropathy has now commenced.