Differential effects on locomotor-like movements of paraplegic rats produced by activation of 5-HT2 or 5-HT7 receptors

• Autorzy: Slawinska U. , Miazga K. , Majczynski H. , Cabaj A.M. , Jordan L.M.
• Języki publikacji: EN

Abstrakty

EN

There is considerable evidence from research in neonatal and adult rat and mouse preparations to warrant the conclusion that activation of 5-HT2 and 5-HT7 receptors leads to activation of the spinal cord circuitry for locomotion. Both types of receptors are involved in control of locomotor movements, but it is not clear how they are implicated in the responses to 5-HT agonists observed after spinal cord injury. Here we used different agonists that are known to be efficient in promoting locomotor recovery in paraplegic rats: 8-OHDPAT (acting on 5-HT7) and quipazine (acting on 5-HT2 receptors). Motor performance was tested before and 15 – 30 min after i.p. drug application in spinal rats placed with the forequarters on a platform above a treadmill while the hindlimbs were touching the moving treadmill belt. Tail pinching was used to induce hindlimb movements that were monitored using video recordings synchronized with simultaneous EMG recordings from the soleus and tibialis anterior muscles of both legs. The application of either 5-HT receptor agonist improved hindlimb plantar walking. Analysis of intra- and interlimb coordination confirmed that the motor performance was significantly better, but in slightly different ways, after application of either drug. Interlimb coordination (left-right coordination) was significantly better after 8-OHDPAT, and the activity of antigravity soleus muscle was significantly longer during locomotor-like movement enhanced by quipazine (an improvement in intralimb coordination). Our results suggest that 5-HT2 and 5-HT7 receptors both facilitate activity in the spinal circuitry controlling locomotion, but their effects are likely exerted on different populations of spinal neurons. These agonists also have affinity to other types of receptors (e.g., 8-OHDPAT acts also on 5-HT1a receptors and quipazine also has affinity for 5-HT3 receptors), so further experiments are needed to substantiate the roles of 5-HT2a and 5-HT7 receptors.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2011
• Tom: 71
• Numer: S
• Opis fizyczny: p.83-84

Twórcy

autor

Slawinska U.

• Department of Neurophysiology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland

autor

Miazga K.

• Department of Neurophysiology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland

autor

Majczynski H.

• Department of Neurophysiology, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland

autor

Cabaj A.M.

• Department of Bionic, Institute of Biocybernetics and Biomedical Engineering PAS, Warsaw, Poland

autor

Jordan L.M.

• Department of Physiology, University of Manitoba, Winnipeg, Manitoba, Canada

Uwagi

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