Fig. 4: Cocaine-induced cellular Ca2+ dependent fluorescence changes in neuronal \((\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(N)}}}}}})\) and astrocytic \((\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(A)}}}}}})\) mice.
From: Cocaine’s cerebrovascular vasoconstriction is associated with astrocytic Ca2+ increase in mice
a, b Time lapse images of Ca2+ fluorescence ratio changes \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(N)}}}}}}\) (ii-v) and \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(A)}}}}}}\) (ii–v) in response to cocaine (1 mg/kg, i.v) superposed on their baseline spectral images (i) obtained at λ1 = 568 nm. Five Regions of interest (ROIs) were selected from fluorescence expressing regions (e.g., pink dots) and one ROI from outside expressing area (e.g., white triangle), that was used to correct for confounding artifacts. c Cocaine-induced mean Ca2+ fluorescence changes in neurons (\(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(N)}}}}}}\), solid line, n = 5), and astrocytes (\(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(A)}}}}}}\) dash line, n = 5), both showing immediate ΔF/FCa2+ increases after cocaine (1 mg/kg, i.v). The \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(N)}}}}}}\) increase was robust and returned to baseline within ~30 min, whereas the \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(A)}}}}}}\) increase was smaller (~2%) but longer lasting. d Comparison of peak increases in \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(N)}}}}}}\) vs \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(A)}}}}}}\), show that the astrocytic response to cocaine was lower than the neuronal response (p*=0.032). e Comparison of recovery time between \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(N)}}}}}}\) and \(\Delta {F/F}_{{{{\rm{Ca}}}^{2+}}{\mbox{-}{{{\rm{G(A)}}}}}}\) indicated that the astrocytic response was longer lasting than the neuronal response (p*<0.001). All error bars are presented as means ± SEM.
