Effects of acetyl- and proprionyl-L-carnitine on peripheral nerve function and vascular supply in experimental diabetes.
L-Carnitine metabolism is abnormal in diabetes mellitus, and treatment with acetyl-L-carnitine (ALC) improves the function of cardiac muscle, retina, and peripheral nerve in experimental models. The aim was to compare the effects of ALC and proprionyl-L-carnitine (PLC) on motor and sensory nerve conduction in streptozotocin-diabetic rats and to ascertain whether their action could be mediated by a vascular mechanism. ALC and PLC treatment for 2 months after diabetes induction attenuated the development of sciatic motor nerve conduction velocity (NCV) deficits by 59.4% +/- 4.4% and 46.9% +/- 3.2%, respectively. There was a similar level of protection for sensory saphenous NCV (42.9% +/- 6.6% and 47.8% +/- 6.0%, respectively). Neither ALC nor PLC prevented the development of resistance to hypoxic conduction failure (RHCF) in sciatic nerve from diabetic rats. A 46.5% +/- 3.4% deficit in sciatic endoneurial blood flow, measured by microelectrode polarography and hydrogen clearance, in diabetic rats was partially prevented by both ALC (48.7% +/- 6.4%) and PLC (69.4% +/- 10.1%). ALC had no significant effect on blood flow in nondiabetic rats. Thus, the data show that these L-carnitine derivatives have a similar efficacy in preventing nerve dysfunction, which depends on a neurovascular action.
Cotter
M A
MA
Department of Biomedical Sciences, University of Aberdeen, Scotland, UK.
Cameron
N E
NE
Keegan
A
A
Dines
K C
KC
D000108:Acetylcarnitine / Q000494:pharmacology* / Q000627:therapeutic use; D000200:Action Potentials; D000818:Animals; D001783:Blood Flow Velocity; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002331:Carnitine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000503:physiopathology*; D007700:Kinetics; D008297:Male; D009431:Neural Conduction / Q000187:drug effects; D010525:Peripheral Nerves / Q000098:blood supply* / Q000187:drug effects / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000098:blood supply / Q000503:physiopathology
D001786:Blood Glucose; C003223:propionylcarnitine; D000108:Acetylcarnitine; D002331:Carnitine