| First Author | Liu J | Year | 2009 |
| Journal | J Neurophysiol | Volume | 102 |
| Issue | 1 | Pages | 337-48 |
| PubMed ID | 19458153 | Mgi Jnum | J:309858 |
| Mgi Id | MGI:6708138 | Doi | 10.1152/jn.91239.2008 |
| Citation | Liu J, et al. (2009) Spinal 5-HT7 receptors are critical for alternating activity during locomotion: in vitro neonatal and in vivo adult studies using 5-HT7 receptor knockout mice. J Neurophysiol 102(1):337-48 |
| abstractText | 5-HT7 receptors have been implicated in the control of locomotion. Here we use 5-HT7 receptor knockout mice to rigorously test whether 5-HT acts at the 5-HT7 receptor to control locomotor-like activity in the neonatal mouse spinal cord in vitro and voluntary locomotion in adult mice. We found that 5-HT applied onto in vitro spinal cords of 5-HT7+/+ mice produced locomotor-like activity that was disrupted and subsequently blocked by the 5-HT7 receptor antagonist SB-269970. In spinal cords isolated from 5-HT7-/- mice, 5-HT produced either uncoordinated rhythmic activity or resulted in synchronous discharges of the ventral roots. SB-269970 had no effect on 5-HT-induced rhythmic activity in the 5-HT7-/- mice. In adult in vivo experiments, SB-269970 applied directly to the spinal cord consistently disrupted locomotion and produced prolonged-extension of the hindlimbs in 5-HT7+/+ but not 5-HT7-/- mice. Disrupted EMG activity produced by SB-269970 in vivo was similar to the uncoordinated rhythmic activity produced by the drug in vitro. Moreover, 5-HT7-/- mice displayed greater maximal extension at the hip and ankle joints than 5-HT7+/+ animals during voluntary locomotion. These results suggest that spinal 5-HT7 receptors are required for the production and coordination of 5-HT-induced locomotor-like activity in the neonatal mouse and are important for the coordination of voluntary locomotion in adult mice. We conclude that spinal 5-HT7 receptors are critical for alternating activity during locomotion. |
