Elevated expression of neurotrophin-3 mRNA in sensory nerve of streptozotocin-diabetic rats

Decreased expression of NT-3 mRNA in the sciatic nerve and leg muscles of s treptozotocin (STZ)-diabetic rats has been associated with the pathogenesis of diabetic neuropathy. The aim of this study was to determine whether STZ -induced diabetes also affects the expression of NT-3 mRNA in the central a nd peripheral projections of sensory nerves. Competitive reverse transcript ion-polymerase chain reaction (cRT-PCR) was used to quantify the levels of NT-3 mRNA in the dorsal root, sural nerve, sciatic nerve and foot skin of a ge-matched and 12-week STZ-diabetic rats. Diabetes increased by 52% (P < 0. 05) the expression of NT-3 mRNA in the dorsal root and sural nerve. It is p roposed that diabetes-induced sensory nerve damage may elevate NT-3 mRNA pr oduction which may act as a source of neurotrophic support for sensory axon s whose target-derived supply of NT-3 may be impaired. (C) 1999 Elsevier Sc ience Ireland Ltd. All rights reserved.