Fig. 2. In vivo halothane challenge of wild-type (WT) and R163C heterozygous (Het) mice. ( A ) Hyperacute rigor mortis of a representative R163C Het mouse evidenced by contracture of skeletal muscles, notably the face, neck, and limbs. ( B ) Rectal temperature of R163C Het (▪) and control (•) mice after exposure to halothane. Data are pooled into 1-min bins and displayed with SDs. The period of exposure to halothane is denoted by the bar above. ( C ) Rectal temperatures of WT and R163C Het mice before ( white bars ) and immediately after terminating the exposure to 42°C ( black bars ).