Fig. 3: Deep brain stimulation (DBS)-evoked hypothermia protected ischaemic brain.
a Schematic representation of a bipolar electrode trajectory to the bilateral medial preoptic nucleus (MPN). b Coronal brain section showing the preoptic area (POA) sites injected with Evens blue (blue dots, red arrow). Scale bar = 2 mm. b’ Electrical lesioning for DBS stimulation site. The brain section stained with crystal violet was superimposed with outlines for the POA structures to indicate the location of MPN (red arrow). c Schematic of experimental design. d The plot showed the Tcore of DBS mice stimulated with various voltages at 100 Hz. e The plot showed Tcore of DBS mice stimulated with various frequencies at 4 V. The Pearson’s correlation between the Tcore with voltages (f) and frequencies (g) was shown. h The entire time course of DBS-evoked hypothermia. The green-coloured areas in d, e, h indicated the time-domain of DBS. The purple-coloured areas in h–k indicated the duration of stable Tcore at 33 °C. VO2 consumption (i), RER (j), and heat level (k) of DBS mice (red coloured lines) and untreated control mice (black-coloured lines) were measured using indirect calorimetry (n = 5 mice). The quantifications of fold reduction during the targeted hypothermia time, as indicated by the purple-coloured areas, are shown in l. m Micrographs of coronal brain sections stained with TTC to show viable tissues (red colour) and damaged tissues (white colour). Scale bar = 4.5 mm. Quantifications of infarction volume (n), oedema volume (o), neurological deficit scores (p), and the forepaw grip strength (q). 1ANOVA with Tukey’s post hoc test with specific P values as indicated in the graph. Data were mean ± s.e.m. (n = 5 mice). Source data are provided as a Source Data file.
