Selenium-induced changes on rat sciatic nerve fibers: compound action potentials.
The nervous system, through its important role as a communication network, governs reactions to stimuli, processes information and generates elaborate patterns of signals to control complex behaviors. Although selenium (Se) was shown to have some beneficial effects in pathological conditions, it is still a toxic element with a fairly small therapeutic window. In this study, the direct effects of Se ranging from 10(-8) to 10(-4) M were tested on rat sciatic nerve preparations. The toxicity started at 10(-8) M and the degree of alterations was found to be dose-dependent. In between the measured parameters, total compound action potential area (Astart = 3.70 +/- 0.16 ms x mV and A(-8) M = 3.04 +/- 0.14 ms x mV) and maximum depolarization points (MDstart = 6.70 +/- 0.22 mV and MD(-8) M = 6.04 +/- 0.18 mV) were the first to be affected from 10(-8) M. Latencies and conduction velocity distribution measurements have shown that nerve fibers having intermediate conduction velocities (20-35 m/s) are the first to be affected from this toxicity. Despite the fact that the new claims concluded the positive effects of the administrations, it is evident that the dose of supplementation must be fine-tuned to avoid possible side effects.
Ayaz
Murat
M
Department of Biophysics, Meram Medical Faculty Selcuk University, Konya, Turkey. ayaz72@yahoo.com
Dalkilic
Nizamettin
N
Tuncer
Seckin
S
Bariskaner
Hulagu
H
D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D008297:Male; D009412:Nerve Fibers / Q000187:drug effects / Q000378:metabolism; D009431:Neural Conduction / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000187:drug effects* / Q000378:metabolism; D012643:Selenium / Q000008:administration & dosage / Q000633:toxicity*; D014131:Trace Elements / Q000008:administration & dosage / Q000633:toxicity*
D014131:Trace Elements; D012643:Selenium