Enkephalin-immunoreactive nociceptive neurons in the cat spinal cord.
In this combined electrophysiological-ultrastructural study in the cat spinal cord, we detected enkephalin-like immunoreactivity using internally radio-labelled monoclonal antibodies in functionally characterized neurons which had been filled intracellularly with horseradish peroxidase. Of the 4 neurons included in this study, two were positive for enkephalin immunoreactivity; one was a nociceptive specific neuron in lamina I, the other a wide dynamic range neuron in lamina V. The other two cells were devoid of immunoreactivity for enkephalin; one was a wide dynamic range neuron and the other was a non-nociceptive neuron. These results thus provide a morphological substrate within the spinal dorsal horn for the release of an endogenous opioid following administration of substance P or noxious cutaneous stimulation.
Ribeiro-da-Silva
A
A
Department of Pharmacology, McGill University, Montréal, Qué., Canada.
De Koninck
Y
Y
Cuello
A C
AC
Henry
J L
JL
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001345:Autoradiography; D002415:Cats; D003712:Dendrites / Q000187:drug effects / Q000648:ultrastructure; D004558:Electric Stimulation; D004745:Enkephalins / Q000276:immunology / Q000378:metabolism*; D006735:Horseradish Peroxidase; D008297:Male; D009474:Neurons / Q000276:immunology / Q000378:metabolism*; D009619:Nociceptors / Q000276:immunology / Q000378:metabolism*; D010812:Physical Stimulation; D013116:Spinal Cord / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D013373:Substance P / Q000378:metabolism
D000911:Antibodies, Monoclonal; D004745:Enkephalins; D013373:Substance P; D006735:Horseradish Peroxidase