Inhibition of Locomotion in Lampreys

Cross references:      GABA/Glycine Inhibition     Tonic Inhibition    
Amphioxus Locomotion       Lamprey Locomotion      
Activity of Reticulospinal Neurons During Locomotion      
Initiation of Locomotion in Lampreys    
Diencephaloreticular Transmission    
Salamander Locomotion    

Reticulospinal neurones provide monosynaptic glycinergic inhibition of spinal neurones in lamprey.   
In lamprey, distinct groups of reticulospinal neurones utilize different neurotransmitters such as glutamate or serotonin. The present study demonstrates that a group of reticulospinal neurones inhibit their target neurones by an action on glycine receptors.  
    Simultaneous intracellular recordings from a reticulospinal neurone and spinal target neurone shows that the former may evoke an IPSP in the latter. These IPSPs are elicited at a constant latency and amplitude, and follow high frequency stimulation (100 Hz). Furthermore, the IPSPs are maintained when the excitatory amino acid synaptic transmission is blocked, suggesting that the effects are not elicited via a powerful disynaptic pathway.  
    These data taken together establish the monosynaptic nature of the pathway. IPSPs elicited from single reticulospinal neurones or from electrical stimulation of the reticular formation are suppressed by administration of strychnine, suggesting that glycine is the neurotransmitter of these inhibitory reticulospinal neurones."  
My comment:   
    The inhibitory neurotransmitter seems to be glycine rather than GABA, however, this reference seems to be using bath-applied ligands in addition to electrical stimulation and monitoring.     
    147 Related citations:   
See PubMed abstract page. 

Descending GABAergic projections to the mesencephalic locomotor region in the lamprey Petromyzon marinus.  

    "These results suggest that the GABAergic projections to the MLR modulate the activity of MLR neurons, which would be inhibited by GABA at rest."  
    See:   GABA/Glycine Inhibition  .     

    Free Article   
Diencephalic Locomotor Region in the Lamprey      
    See:  Diencephaloreticular Transmission  for full Abstract, Related citations, Cited by's, 
Important highlights and Free Full Text  . 
      Free text with excised reference links.   

Evolution of the basal ganglia: dual-output pathways conserved throughout vertebrate phylogeny.
    See:   GABA/Glycine Inhibition  . 

SubC: Inhibition of Locomotion 
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