Nerve function in experimental diabetes in rats: effects of electrical stimulation.
The effects of unilateral electrical stimulation of the peroneal sciatic nerve branch were studied in streptozocin-diabetic rats of 12-wk duration. Stimulation was carried out over 7 days (10 Hz, 8 h/day) with chronically implanted electrodes. Compared with controls, there was a 25% conduction velocity (CV) deficit for the peroneal nerve supplying tibialis anterior muscle in the unstimulated leg, which was corrected by stimulation. For tibial fibers supplying soleus muscle, a similar diabetic CV deficit (20%) was normalized by stimulation, although soleus axons were not directly activated. In saphenous nerve, which has a functionally separate vascular supply, peroneal stimulation was ineffective. In anesthetized diabetic rats, stimulation caused an 18% reduction in tibialis anterior CV after 4 h. However, serial measurements showed progressive normalization of CV over 4 days of stimulation. On termination, CV returned to diabetic levels over 36-60 h. Sciatic nerve showed a 70% increase in resistance to hypoxic conduction failure with diabetes, which was halved by chronic stimulation. Acute experiments demonstrated that peroneal stimulation increased sciatic vascular conductance by 60%. We conclude that stimulation causes activity-related improvements in diabetic nerve blood flow and metabolism.
Cameron
N E
NE
Department of Biomedical Sciences, University of Aberdeen, Scotland, United Kingdom.
Cotter
M A
MA
Robertson
S
S
Maxfield
E K
EK
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D004558:Electric Stimulation; D007511:Ischemia / Q000503:physiopathology; D008297:Male; D009420:Nervous System / Q000503:physiopathology*; D009431:Neural Conduction; D010543:Peroneal Nerve / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012039:Regional Blood Flow; D012584:Sciatic Nerve / Q000098:blood supply / Q000503:physiopathology; D013979:Tibial Nerve / Q000503:physiopathology; D013997:Time Factors