Extended Data Fig. 6: Propranolol has no effect on cellular calcium activity but reduces lactate surge in astrocytes and neurons (Related to Fig. 3).

(a) Protocol used to investigate the effects of propranolol in neurons and astrocytes. Propranolol (10mg per kg, i.p.) was injected after baseline acquisition (0 h) and the same cells were imaged in subsequent sessions 1, 3, 6 and 24 h after injection. (b–e) ISO pulse-evoked calcium changes in neurons (b, c) and astrocytes (d, e) at different time points. Signal amplitudes did not differ from control experiments with saline injections (Extended Data Fig. 7). m = 6 experiments used for statistical analysis. (f, g) Temporal comparison of neuronal calcium and astrocytic lactate response before (0 h; black) and 6 h after (red) propranolol injection. Propranolol had no effect on neuronal calcium response (f) and the initial dip in astrocytic lactate upon arousal but it reduced the second phase of lactate mobilization by reducing the astrocytic lactate surge (g). Only means are displayed. (h) The fraction of astrocytes showing a dip and the fraction of astrocytes and neurons showing an activity-dependent surge. (i) The area under the curve (AUC) in responding astrocytes and the AUC of the surge of responding astrocytes and neurons. The threshold for a lactate dip (T5.2) or surge (T7) detection was set to 2 SD from baseline values (T2). The same 113 neurons and 118 were monitored for each paradigm. N = number of animals, n = number of experiments. Data is represented as mean ± SD. m = 113 neurons and 118 astrocytes for lactate measurements used to derive statistics. Mean statistics were calculated using two-tailed linear mixed-effects models and Tukey’s post hoc tests.