gms | German Medical Science

61st Annual Meeting of the German Society of Neurosurgery (DGNC) as part of the Neurowoche 2010
Joint Meeting with the Brazilian Society of Neurosurgery on the 20 September 2010

German Society of Neurosurgery (DGNC)

21 - 25 September 2010, Mannheim

Inhibition of the intrinsic component of the sympathetic nervous system impaires cerebral autoregulation in a rat AVM model

Meeting Abstract

  • Carsten Stüer - Departments of Neurosurgery, Technische Universität München, Deutschland
  • Toshiki Ikeda - Rheinische Friedrich-Wilhelms Universität Bonn, Deutschland
  • Petra Heinrich - Department of Statistics, Technische Universität München, Deutschland
  • Michael Stoffel - Departments of Neurosurgery, Technische Universität München, Deutschland
  • Karl Schaller - Hopitaux Universitaires de Geneve, Switzerland
  • Bernhard Meyer - Department of Statistics, Technische Universität München, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 61. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC) im Rahmen der Neurowoche 2010. Mannheim, 21.-25.09.2010. Düsseldorf: German Medical Science GMS Publishing House; 2010. DocP1841

DOI: 10.3205/10dgnc312, URN: urn:nbn:de:0183-10dgnc3122

Published: September 16, 2010

© 2010 Stüer et al.
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Outline

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Objective: To test the hypothesis that the maintenance of the cerebral autoregulation does not depend on the activity of the sympathetic nervous system (SNS).

Methods: 12 weeks after creation of an extracranial AV-Fistula (Morgan-Type in male Sprague-Dawley rats) (n=40) or sham operation (n=40) rSO2 (spectrophotometry), rCBF (LDF) and MAP were measured continuously. Norepinephrine was administered systemically for static testing of autoregulation before and after fistula occlusion. N=10 fistula or sham animals each underwent 1. no SNS manipulation, 2. extrinsic SNS inhibition via bilateral sympathectomy, 3. intrinsic SNS inhibition via the neurotoxin DSP-4 or 4. complete SNS inhibition. Generalized estimation equations (GEE) were used to estimate the dependency of MAP, rCBF and rSO2.

Results: Within the sham group a maintained cerebral autoregulation could be tested for all animals. Within the fistula rats, a dependency between rCBF/rSO2 and MAP was proven (P<0.001) for animals after inhibition of the intrinsic and complete cerebral noradrenergic system before occlusion of the fistula. After occlusion of the fistula, an impaired cerebral autoregulation could only be tested for DSP-4 treated rats.

Conclusions: For the first time, an impaired cerebral autoregulation under conditions of an altered SNS could be tested in vivo in a rat AVM model. Autoregulation trials suggest the predominant role of the intrinsic noradrenergic system as with inhibition of the extrinsic component of the SNS does not affect cerebral autoregulation.