S. Croul et al., NK1, NMDA, 5HT1a, and 5HT2 receptor binding sites in the rat lumbar spinalcord: Modulation following sciatic nerve crush, EXP NEUROL, 154(1), 1998, pp. 66-79
Quantitative receptor binding autoradiography was used to study the NK1, NM
DA, 5HT1a, and 5HT2 receptor binding densities in the adult rat lumbar spin
al cord from 3 days to 20 weeks following a unilateral crush lesion of the
sciatic nerve. NK1 binding density increased unilaterally in the superficia
l dorsal horn on the side of the sciatic crush to reach levels 60% above co
ntrols by 4 weeks following the lesion and returned to control values by 12
weeks. NMDA binding density increased bilaterally and equally in both the
dorsal and ventral horns to reach 300% of control values at 2 weeks followi
ng the crush and returned to near control values by 20 weeks following the
lesion. Serotonergic receptor binding did not change. The changes in NK1 re
ceptor binding density on postsynaptic dorsal horn cells are consistent wit
h a response to the decrease and recovery in the synthesis and transport of
tachykinins by the dorsal root ganglion cells following peripheral nerve i
njury. The bilateral changes in NMDA receptor binding are more likely media
ted by polysynaptic pathways in the spinal cord that respond to the changes
in metabolic events of the dorsal root ganglion cells evoked by axotomy an
d regeneration. (C) 1998 Academic Press.