Neurokinin A, calcitonin gene-related peptide, and dynorphin A (1-8) in spinal dorsal horn contribute to descending inhibition evoked by nociceptive afferent pathways: an immunocytochemical study.
Immunocytochemical technique was used to compare the contents of neurokinin A (NKA), calcitonin gene-related peptide (CGRP), and dynorphin A (1-8) (DynA) on two sides of the lumbar dorsal horn of rats in which the unilateral thoracic dorsalateral funiculus (DLF) was transected while formalin (0.2 ml, 0.5%) was injected equally into two hindpaws. The results showed that all the NKA-like, CGRP-like, and DynA (1-8)-like immunoreactivities were significantly lower in the superficial laminae of the dorsal horn on the side ipsilateral to the lesioned DLF than that on the side with intact DLF. This implies that peripheral noxious inputs activate the supraspinal descending inhibitory systems which in turn modulate the transmission of noxious message at the spinal level by changing the release of related neuropeptides.
Wang
H
H
Department of Neurobiology, Shanxi Medical University, Taiyuan, Shanxi, People's Republic of China.
Wang
R
R
Nie
H
H
Zhang
R
R
Qiao
J T
JT
D000344:Afferent Pathways / Q000502:physiology*; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism*; D004399:Dynorphins / Q000378:metabolism*; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D008159:Lumbar Vertebrae / Q000378:metabolism* / Q000473:pathology; D008297:Male; D015288:Neurokinin A / Q000378:metabolism*; D010147:Pain Measurement; D010446:Peptide Fragments / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D010446:Peptide Fragments; D004399:Dynorphins; C026770:dynorphin (1-8); D015288:Neurokinin A; D015740:Calcitonin Gene-Related Peptide