Myocardial effects of halothane and sevoflurane in diabetic rats.
BACKGROUND
Diabetes induces significant myocardial abnormalities, but the effects of halogenated anesthetics on this diseased myocardium remain a matter of debate.


METHODS
Left ventricular papillary muscles and triton-skinned cardiac fibers were provided from control and streptozotocin-induced diabetic rats. The effects of halothane and sevoflurane were studied on inotropic and lusitropic responses, under low (isotony) and high (isometry) loads in papillary muscles and then on isometric tension-Ca2+ concentration (pCa) relations obtained in triton-skinned cardiac fibers. Data are presented as mean +/- SD.


RESULTS
Sevoflurane and halothane induced a negative inotropic effect that was more important in diabetic rats (active force: 1.5% halothane, 19+/-6 vs. 24+/-6% of baseline, P < 0.05; 3.6% sevoflurane, 47+/-14 vs. 69+/-17% of baseline, P < 0.05). However, when differences in minimum alveolar concentration were considered, no significant difference was observed between groups for halothane. The effects of halothane and sevoflurane on isotonic relaxation and postrest potentiation were not significantly different between groups. In contrast, the decrease in Ca myofilament sensitivity produced by each anesthetic agent was greater in diabetic rats than in control rats (0.65% halothane, -0.15+/-0.07 vs. -0.05+/-0.04 pCa unit, P < 0.05; 1.8% sevoflurane, -0.12+/-0.06 vs. -0.06+/-0.04 pCa unit, P < 0.05).


CONCLUSIONS
The negative inotropic effect of halothane and sevoflurane was greater in diabetic rats, mainly because of a significant decrease in myofilament Ca sensitivity.
David
Jean-Stéphane
JS
Laboratoire d' Anesthésiologie, Département d' Anesthésie-Réanimation, Centre Hospitalier Universitaire Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Université Pierre et Marie Curie, Paris, France.
Tavernier
Benoît
B
Amour
Julien
J
Vivien
Benoît
B
Coriat
Pierre
P
Riou
Bruno
B
D000818:Animals; D003864:Depression, Chemical; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D004305:Dose-Response Relationship, Drug; D006221:Halothane / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D009200:Myocardial Contraction / Q000187:drug effects* / Q000502:physiology; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D000077149:Sevoflurane
D008738:Methyl Ethers; D000077149:Sevoflurane; D006221:Halothane