Fig. 7. Fura-2 fluorescence (top trace), an index of [Ca2+], and cell length (bottom trace), an index of contraction, were measured simultaneously in an electrically stimulated rat ventricular myocyte. Application of halothane initially induced a transient increase in the Ca2+transient and twitch force before both the Ca2+signals and contraction decreased. Reproduced with permission from Prof. M. R. Boyett and the Journal of Physiology.