EFFECTS OF VOLATILE ANESTHETICS ON HIPPOCAMPAL SLICE METABOLISM, RESPONSE TO ANOXIA WITH AND WITHOUT GLUCOSE

Anesthetics attenuate ischemic damage and so are often not used when p reparing hippocampal slices for studies of ischemic or anoxic damage. In this study, we tested whether halothane, ether or isoflurane, when used briefly during slice preparation, have persistent effects on slic e ATP metabolism, protein synthesis or morphology. We also tested the effects of anoxia with and without glucose on these slices. Five minut es of anoxia without glucose (anoxia-aglycemia) caused a dramatic depl etion of ATP to less than 22% of control levels, a persistent inhibiti on of neuronal protein synthesis to less than 10% of control rates and severe morphological damage. Slices prepared using volatile anestheti cs showed the same degree of damage due to anoxia-aglycemia, when comp ared with untreated tissue. In contrast, 5 min anoxia caused a 40% dec rease in ATP levels in untreated tissue, but did not damage protein sy nthesis or morphology. While isoflurane-treated tissue responded ident ically to anoxia as untreated tissue, both halothane and ether prevent ed the anoxic ATP fall. These findings suggest that while halothane an d ether may have persistent effects on slice responses to anoxia, isof lurane is a good candidate anesthetic for slice preparation procedures .