Fig. 5

Ketamine triggers a long-lasting calcium elevation in astroglia (A) Fish expressing the calcium indicator jRGECO1a in astroglia were imaged using an epifluorescence microscope before and during acute treatment with ketamine for 30 min. (B) Example fluorescence micrographs of jRGECO1a signal at three time points illustrating elevation and return to baseline of cytosolic calcium in the presence of ketamine. Scale bar, 50 μm. (C) Heatmap of glial jRGECO1a signal in four ROIs (left) for fish in (C). Pink bar indicates ketamine in the bath. (D) Hindbrain jRGECO1a fluorescence change in an example fish treated with ketamine (200 μg/mL) or vehicle (control). Short increases in astrocytic calcium during struggles in control fish are indicated by gray arrowheads. (E) Average hindbrain fluorescence change following treatment with listed compounds. Ketamine, but not fluoxetine (SSRI), DOI (5-HT2AR agonist), or MS-222 (anesthetic), elevates cytosolic astroglial calcium. One-way ANOVA with Tukey’s multiple comparison test (vs. control). n = 5 (control, MS-222), 4 (all other conditions). p = 0.0169 (ketamine), 0.9395 (MS-222), 0.9893 (DOI), 0.9996 (fluoxetine). (F) Summary of findings.