RT Journal Article
SR Electronic
T1 Is Hydrogen Sulfide-Induced Suspended Animation General Anesthesia?
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 735
OP 742
DO 10.1124/jpet.111.187237
VO 341
IS 3
A1 Rosie Q. Li
A1 Andrew R. McKinstry
A1 Jason T. Moore
A1 Breanna M. Caltagarone
A1 Maryellen F. Eckenhoff
A1 Roderic G. Eckenhoff
A1 Max B. Kelz
YR 2012
UL http://jpet.aspetjournals.org/content/341/3/735.abstract
AB Hydrogen sulfide (H2S) depresses mitochondrial function and thereby metabolic rates in mice, purportedly resulting in a state of “suspended animation.” Volatile anesthetics also depress mitochondrial function, an effect that may contribute to their anesthetic properties. In this study, we ask whether H2S has general anesthetic properties, and by extension, whether mitochondrial effects underlie the state of anesthesia. We compared loss of righting reflex, electroencephalography, and electromyography in mice exposed to metabolically equipotent concentrations of halothane, isoflurane, sevoflurane, and H2S. We also studied combinations of H2S and anesthetics to assess additivity. Finally, the long-term effects of H2S were assessed by using the Morris water maze behavioral testing 2 to 3 weeks after exposures. Exposure to H2S decreases O2 consumption, CO2 production, and body temperature similarly to that of the general anesthetics, but fails to produce a loss of righting reflex or muscle atonia at metabolically equivalent concentrations. When combined, H2S antagonizes the metabolic effects of isoflurane, but potentiates the isoflurane-induced loss of righting reflex. We found no effect of prior H2S exposure on memory or learning. H2S (250 ppm), not itself lethal, produced delayed lethality when combined with subanesthetic concentrations of isoflurane. H2S cannot be considered a general anesthetic, despite similar metabolic suppression. Metabolic suppression, presumably via mitochondrial actions, is not sufficient to account for the hypnotic or immobilizing components of the anesthetic state. Combinations of H2S and isoflurane can be lethal, suggesting extreme care in the combination of these gases in clinical situations.