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07:56
Measuring Skeletal Muscle Thermogenesis in Mice and Rats
Published on: July 27, 2022
Day-night difference in thermoregulatory responses to olfactory stimulation
Mamoru Tanida1, Jiao Shen, Takuo Nakamura
1Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan. mtanida@sk.ritsumei.ac.jp
Neuroscience Letters
|June 3, 2008
Summary
Olfactory stimulation with grapefruit or lavender scents affects brown adipose tissue temperature differently during the day versus night in rats. The suprachiasmatic nucleus (SCN) plays a role in mediating these scent-induced thermoregulation responses.
Area of Science:
- Neuroscience
- Chronobiology
- Physiology
Background:
- Olfactory stimulation can influence thermoregulation, affecting brown adipose tissue temperature (BAT-T).
- Previous studies in mice showed scent of grapefruit oil (SGFO) elevated BAT-T, while scent of lavender oil (SLVO) lowered it.
Purpose of the Study:
- To investigate the day-night differences in the effects of SGFO and SLVO on BAT-T and body temperature (BT) in rats.
- To determine the role of the suprachiasmatic nucleus (SCN) in mediating these olfactory-induced thermoregulatory responses.
Main Methods:
- Conscious rats were exposed to SGFO or SLVO during the light (14:00) and dark (2:00) periods.
- BAT-T and abdominal body temperature (BT) were continuously monitored.
- Responses were also assessed in rats with bilateral lesions of the suprachiasmatic nucleus (SCN) and changes in sympathetic nerve activity innervating brown adipose tissue (BAT-SNA) were measured.
Main Results:
- During the light period, SLVO suppressed BAT-T and BT, while SGFO elevated them.
- During the dark period, neither SGFO nor SLVO significantly altered BAT-T or BT.
- SCN lesions abolished the day-night differences in BAT-T and BT responses to both SGFO and SLVO, and also eliminated changes in BAT-SNA.
Conclusions:
- There is a distinct day-night difference in the thermoregulatory effects of SGFO and SLVO in rats.
- The suprachiasmatic nucleus (SCN) is critically involved in mediating these scent-induced changes in BAT-T, BT, and BAT-SNA.
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