Fig. 6. In vitro metabolism of methoxycarbonyl etomidate in pooled brain tissue and cerebrospinal fluid (CSF) from rats. Each brain tissue data point is the mean value from three experiments using a single source of pooled brain tissue derived from four rats. Each CSF data point is the mean value obtained from four separate experiments using CSF drawn from four rats. The lines are nonlinear least squares fits of the data assuming a first-order process with the maxima and minima constrained to 100 and 0, respectively. The metabolic half-lives of methoxycarbonyl etomidate in brain tissue and CSF were determined to be 11 min (95% CI 10–13 min) and 20 min (95% CI 16–27 min), respectively.