Isoflurane activates the type 1 ryanodine receptor to induce anesthesia in mice
Fig 5
Inhibition of neuronal RyR1 alters the responses to isoflurane.
(A) AAV-mediated expression in the brain. (B) Dose–response curves for loss of righting reflex (LORR) of mice expressing mCherry or RyR1-BsSV. Data were fitted with logistic functions (equation 5 in Materials and methods). N = 18 for each group. The shaded regions represent 95% CIs. (C) Comparison of the concentrations at which mice reach LORR (Mean ± SD with individual data points). N = 18 for each group. The P-value by the Student t test is shown. (D) Cultures of cortical neurons on HD-MEA. (E, F) Representative raster plots and the total spike counts in baseline (E) and the isoflurane treatment (2.1% isoflurane) (F). (G) Raster plots across the sequential exposure to isoflurane and the recovery for mCherry and RyR1-BsSV expressions. The above black bars represent the detected prolonged burst periods. Four independent wells are indicated, respectively. The extracellular calcium concentration was adjusted to 2.0 mM before the experiment. (H) Duration of the prolonged burst periods. Data are presented as Mean ± SD with individual data points. N = 4 for both mCherry (gray) and RyR1-BsSV (red) expressions. *P < 0.05 by the two-sample Wilcoxon test. Camk2a, Ca2+/calmodulin-dependent protein kinase II α; AAV, adeno-associated virus; RyR1-BsSV, brain-specific splicing variant of the type 1 ryanodine receptor; Iso., Isoflurane; LORR, loss of righting reflex; HD-MEA, high-density multielectrode array; Recov., Recovery. The mice illustration was modified from Openclipart (https://openclipart.org/).