Fig. 3. Effects of 1 minimum alveolar concentration halothane, isoflurane, or sevoflurane on the lusitropic response under low load to β-adrenoceptor stimulation in healthy (  A ) and diabetic (  B ) rats. R1 = ratio of maximum shortening velocity (^maxVc) to maximum lengthening velocity (^maxVr), tested the lusitropic effect under low load. The control group was not exposed to halogenated anesthetics. Data are presented as mean percentage of baseline value ± SD.