Investigating the role of hypothalamic paraventricular nucleus in nociception of the rat.
The role of hypothalamic paraventricular nucleus (PVN) in nociception was investigated in the rat. Electrical stimulation of the PVN increased pain threshold, and microinjection of L-glutamate sodium into the PVN also elevated pain threshold in a dose-dependent manner, whereas cauterization of the PVN decreased pain threshold. Stimulation or cauterization of the area located within 1.0 mm of the outer perimeter of the PVN did not change pain threshold. Pituitary removal could not influence the effect of L-glutamate sodium microinjection into PVN-induced pain threshold increase. The data suggest that PVN plays a role in antinociception through the central nervous system rather than peripheral organs.
Yang
Jun
J
Guangdong Bangmin Pharmaceutical Co. Ltd., Institute for Pharmaceutical and Medical Science, Jiangmen, Guangdong, China. yj6676@yahoo.com
Chen
Jian-Min
JM
Yang
Yu
Y
Liu
Wen-Yan
WY
Song
Cao-You
CY
Lin
Bao-Cheng
BC
D000818:Animals; D004558:Electric Stimulation; D008297:Male; D008845:Microinjections; D009619:Nociceptors / Q000502:physiology*; D017288:Pain Threshold; D010286:Paraventricular Hypothalamic Nucleus / Q000033:anatomy & histology* / Q000502:physiology*; D010902:Pituitary Gland / Q000601:surgery; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors