The responses of dorsal horn neurones to controlled mechanical stimulation of the hindlimb skin in the rabbit.
Seven types of neurones responding to mechanical stimulation of the hindlimb skin were identified in the dorsal horn of the spinal cord of the rabbit. Of the 218 units examined, 33% were activated by movement of hairs--H cells; 25% were excited by stimulation of Type I domes--on/off cells; 15.6% were spontaneously active and were excited by vertical displacement of the skin and lateral skin stretch--SPE (spontaneous excited) cells; 4.4% were spontaneously active and were inhibited by mechanical stimulation of the skin--SPI (spontaneous inhibited) cells; 5.2% were spontaneously active and responded to application of pressure--SPEP (spontaneous excited pressure) cells; 3% were spontaneously active and were excited by movement of joints--SPEJ (spontaneous excited joint) and 13.8% of neurones responded to hair movement and also to some other forms of mechanical stimulus--CM (combined mechanosensitive) cells. Of the 218 units examined, 133 were located in lamina IV and 85 in lamina V. A quantitative analysis of some of the characteristics of the on/off, SPE and SPI cells is carried out and a model of the dorsal horn system activated by Type I and Type II receptor units is proposed.
D000818:Animals; D004558:Electric Stimulation; D005073:Evoked Potentials, Somatosensory; D005727:Ganglia, Spinal / Q000502:physiology*; D006614:Hindlimb / Q000294:innervation; D008297:Male; D008465:Mechanoreceptors / Q000502:physiology*; D009433:Neural Inhibition; D009474:Neurons / Q000502:physiology; D010812:Physical Stimulation; D051381:Rats; D012684:Sensory Thresholds; D012867:Skin / Q000294:innervation*; D013127:Spinal Nerves / Q000502:physiology*; D013497:Sural Nerve / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission; D014110:Touch / Q000502:physiology