Skip to main content
Fig. 2 | Molecular Brain

Fig. 2

From: Aversive emotion rapidly activates orexin neurons and increases heart rate in freely moving mice

Fig. 2Fig. 2

Aversive stimuli activated orexin neurons together with an increase in heart rate. A Schematic drawing showing the experimental design; intruder stress (left), ultrasound stress (middle), and predator odor (TMT) stress (right). B Results of intruder stress experiment. The horizontal bar shows the time when the intruder was in the experimental chamber for 2 min. (i) (Left) Averaged time course of the heart rate during the intruder test. The mean value is shown in the dark orange line and values of individual animals are shown in light orange. (Right) The bar graph shows averaged values of the heart rate for 1 min during the baseline period and after the introduction of an intruder. (ii) (Left) Averaged time course of the G-CaMP6 fluorescence during intruder test. The mean value is shown in the dark green line and values of individual animals are shown in light green. The horizontal bar shows the time when the intruder was in the experimental chamber. (Right) Bar graph shows averaged values of the intensity of G-CaMP6 fluorescence for 1 min during the baseline period and after the introduction of the intruder. (iii) Results of mCherry fluorescence are shown in a similar manner to B-ii. C Results of the ultrasound stress experiment. Data are shown in a similar manner to B. The horizontal bar shows the time when ultrasound was applied for 2 s. D Results of TMT smell experiment. Data are shown in a similar manner to B. The horizontal bar shows the time when TMT was applied for 2 s. Data were sampled in six animals in the intruder test and ultrasound stimulation and seven animals in the TMT test. Group data are presented as mean ± SEM. P-value was calculated using paired Student’s t-test. E Schematic drawing showing the control experimental design; mice (n = 4) were given ultrasound stress for positive control. Then odorless cotton swab and the empty cage were presented in intervals of 30 min. For randomization, 2 mice received cotton swab for the first time and the other mice received empty cage for the first time. F Traces of the heart rate (upper), G-CaMP6 fluorescence (middle), and fluorescence of mCherry (lower) in ultrasound stress group (left), cotton swab group (middle), and empty cage group (right). The colored line indicates averaged value and the gray line shows SEM. G (Upper) Bar graph showing averaged values of the heart rate for 1 min during the baseline period and after the introduction of an intruder. (Middle) Bar graph showing averaged values of the intensity of G-CaMP6 fluorescence for 1 min during the baseline period and after the introduction of intruder. (Lower) Results of mCherry fluorescence are shown in a similar manner to G-CaMP6. Group data are presented as mean ± SEM. P-value was calculated using paired Student’s t-test

Back to article page