Veterinary Research Communications

, Volume 31, Issue 6, pp 757–763

Isoflurane Potency in the Northern Leopard Frog Rana pipiens is Similar to That in Mammalian Species and is Unaffected by Decerebration

  • L. S. Barter
  • L. O. Mark
  • A. C. Smith
  • J. F. Antognini
Article

DOI: 10.1007/s11259-007-0077-5

Cite this article as:
Barter, L.S., Mark, L.O., Smith, A.C. et al. Vet Res Commun (2007) 31: 757. doi:10.1007/s11259-007-0077-5

Abstract

Amphibians are commonly used in biomedical research, including studies of mechanisms of anaesthetic action. There is, however, little published work describing the kinetics of inhaled anaesthetic agents or the potency of isoflurane in amphibians. Ten Northern leopard frogs were exposed to a constant isoflurane concentration of 1.0%, 1.2% or 1.5% atm for 4 h, and their response to a noxious stimulus was tested every 20 min. Each frog was anaesthetized with each concentration in random order and allowed at least 16 h to recover between anaesthetic exposures. Frogs were then pithed and the protocol was repeated. Frogs first displayed immobility during stimulus application at 80 min, and the proportion of animals becoming immobile steadily increased to reach a stable level at 4 h. The 50% effective dose for isoflurane in intact and pithed frogs did not differ, and was 1.15 and 1.25% atm, respectively. The potency of isoflurane in leopard frogs was similar to that reported in mammalian species. Cutaneous uptake of anaesthetic is effective given sufficient time, approximately 4 h in this study. Forebrain structures appear to be unimportant for the immobilizing action of isoflurane in the frog.

Keywords

amphibianfroganaesthesiainhalantsanaesthetic potencyisoflurane

Abbreviations

ED50

50% effective dose

MAC

minimum alveolar concentration

Copyright information

© Springer Science + Business Media, Inc. 2007

Authors and Affiliations

  • L. S. Barter
    • 1
  • L. O. Mark
    • 2
  • A. C. Smith
    • 1
  • J. F. Antognini
    • 1
  1. 1.Department of Anesthesiology and Pain MedicineUniversity of California Davis
  2. 2.University of Notre DameUSA