Differential responsiveness of c-Fos expression in the rat medulla oblongata to different treadmill running speeds.
Expression of the inducible transcription factor c-Fos was mapped in the rat medulla oblongata to identify the brain areas respond to different running speeds. Rats were subjected to 30 min of running, either at high speed, low speed or just sitting on a treadmill (control). Blood lactate levels were measured to confirm the physiological impact of different exercise intensities. The number of c-Fos-ir cells was counted and their spatial distributions were mapped through the rostral to the caudal level in the medulla. A statistically significant exercise intensity-dependent induction of c-Fos was observed in the nucleus of the solitary tract (NTS) and caudal ventrolateral medulla (CVL) in the medulla. Further, c-Fos induction was more predominant in the caudal part of each nucleus. The present data clearly show that different running speeds cause differential activation of each nucleus in the medulla, and in particular, the caudal parts of the NTS and the CVL are the most responsive to speed changes. The present study identifies brain areas newly found to be responsive to changes in running speed. These findings are likely to be particularly helpful in studies of specific neural circuits and their functions in response to different running speeds.
Ohiwa
Nao
N
Laboratory of Exercise Biochemistry, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennôdai, Tsukuba, Ibaraki 305-8574, Japan.
Saito
Tsuyoshi
T
Chang
Hyukki
H
Nakamura
Toru
T
Soya
Hideaki
H
D000818:Animals; D001835:Body Weight / Q000502:physiology; D005786:Gene Expression Regulation / Q000502:physiology*; D016762:Genes, fos / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D007150:Immunohistochemistry; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008526:Medulla Oblongata / Q000166:cytology / Q000378:metabolism* / Q000502:physiology*; D009474:Neurons / Q000378:metabolism; D005082:Physical Exertion / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012420:Running / Q000502:physiology*; D017552:Solitary Nucleus / Q000502:physiology
D019344:Lactic Acid