VAGUS NERVE STIMULATION REDUCES BODY WEIGHT IN GENETIC ABSENCE EPILEPSY RATS FROM STRASBOURG (GAERS)
Abstract number :
2.445
Submission category :
Year :
2003
Submission ID :
3717
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Stefanie Dedeurwaerdere, Robrecht Raedt, Kristl Vonck, Pieter Claeys, Paul Boon Clinical and Experimental Neurophysiology Lab, University Hospital Ghent, Ghent, Oost Vlaanderen, Belgium
Vagus nerve stimulation is an adjunctive therapy for medically intractable partial seizures with or without secondary generalisation. Stimulation of the vagus nerve also has an influence on mood, cognition and pain. The purpose of this study was to determine the effects of vagal nerve stimulation on weight regulation in a rat model for absence epilepsy.
Genetic Absence Epilepsy Rats from Strasbourg (GAERS, n=10) were implanted with 5 epidural electrodes and a stimulation electrode around the left vagal nerve. The rats were allowed to recover for 1 week. During four weeks after the implantation the rats were weighted every week for three consecutive days. From the second week on, the animals were continuously stimulated for two (n=2) or three (n=3) weeks with the following parameters: 60 sec trains of 0.5 ms monophasic pulses at 30 Hz with a train interval of 12 sec. The other five rats served as control and received no stimulation. The rats were weighted three consecutive days for four weeks after the implantation.
On the week before stimulation, weight did not differ between rats of the control (284 [plusmn] 27 g) and stimulation group (287 [plusmn] 22 g) . During three weeks of continuous stimulation, stimulated rats showed a highly significant loss of body weight (p[lt]0.001). Average weight at the end of the stimulation period was 242 [plusmn] 37 g. This was not the case in the control group, where the average weight was 294 [plusmn] 21 g. In two animals of the stimulation group stimulation was stopped after two weeks. Immediately after stimulation a weight gain was seen in these rats and at the end of the third week their weight didn[rsquo]t differ significantly from the control rats. This was in contrast to the weight of the rats that still received vagal stimulation.
Chronic VNS has a significant influence on weight regulation in a rat model for absence epilepsy. When stimulation is stopped weight slowly retains normal values over a period of one week. Further studies are needed to determine the factors underlying the reduction of body weight in response to VNS.
[Supported by: The following grants: BOF 011D9601, FWO and the Ghent University Epilepsy Grant 1999-2003.]