Effect of hyperglycemia on conduction parameters of tibial nerve’s fibers to different muscles: A rat model

Abstract

Introduction:Routine conduction studies reflect the summation of all nerve fibers in a peripheral nerve. Nerve fiber groups to distal, small muscles have smaller diameters than the ones to large proximal muscles. There may be minimal differences between the diameters of nerve fiber groups innervating different muscles; even they are all same type of fibers. So, in neuropathic processes some nerve fiber groups may be more seriously affected.Materials and Methods:14 rats ( 7 diabetic, 7 control) were studied. Tibial nerve was stimulated from two points and while recorded from a distal (foot intrinsic muscles) and a proximal (gastrocnemius) muscle.Results:There was a significant difference between the proximal and distal recorded conduction velocities. Both proximal and distal recorded conduction velocities decreased during the hyperglycemic process.Discussion:Our method successfully demonstrated different nerve fiber groups; but, the neuropathic process seemed to be homogeneous in both fiber groups.

Evaluation of Electrophysiological Effects of Melatonin and Alpha Lipoic Acid in Rats with Streptozotocine Induced Diabetic Neuropathy

“…Electrophysiological measurements were performed under the intraperitoneal anesthesia (i.p.) with the injection of xilazine (12 mg/kg) and ketamine (75 mg/kg) combination (12). Making the rats diabetic was enabled with the single injection of the total dose as 50 mg/kg i.p streptozotocin.…”

“…Making the rats diabetic was enabled with the single injection of the total dose as 50 mg/kg i.p streptozotocin. Considering that blood glucose values over 300 mg/dl were prevalently accepted as the diabetic values in the former studies, blood glucose values exceeding 300 mg/dl were regarded as the diagnosis criteria of diabetes [12][13][14] and 4 weeks were given for the development of neuropathy after making the rats diabetic. Following 4 weeks, the rats were randomized and 3 treatment groups were created.…”

“…The rats were randomized by including them in 3 groups respectively and the tails of the rats were marked with different colors. Electrophysiological analysis was made after measuring the initial weights of the rats [12,15,16]. 5 rats died within 4 weeks due to the diabetic complications.…”

Comparison of the Nerve Conduction Parameters in Proximally and Distally Located Muscles Innervated by the Bundles of Median and Ulnar Nerves

“…The diameters of the most rapidly conducting fibers differ among the most rapidly conducting nerve fibers innervating a proximal muscle, which has a larger diameter compared to those nerve fibers innervating a distal muscle [ 4 , 6 ]. Consequently, if a nerve is stimulated from the same region and an electrophysiological recording is conducted in one proximally and another distally located muscle, data can be obtained about the conduction parameters of the nerve fibers of various diameters [ 7 ]. Hence, this study was performed to assess nerve conduction velocities, amplitudes of compound muscle action potential (CMAP) and the durations of a proximal forearm muscle with a relatively larger mass and of thenar muscles that were distally localized with a small mass stimulated by the median nerve.…”

Association between clinical condition and F-waves changes in the acute phase of stroke

“…Hyperglycemia in the acute phase of stroke may play a role in ischemic neuronal damage 24 and, additionally, hyperglycemia is associated with a poorer long-term prognosis 25,26,27 . Hyperglycemia has been reported to alter nerve conduction in some preclinical studies 28,29 . In clinical studies, acute hyperglycemia did not alter nerve conduction velocities and amplitudes…”