Only through the brain nuclei, arginine vasopressin regulates antinociception in the rat.
The effect of arginine vasopressin (AVP) on rat antinociception was investigated. Intraventricular injection of 50 or 100 ng AVP dose-dependently increased the pain threshold; in contrast, intraventricular injection of 10 microl anti-AVP serum decreased the pain threshold; both intrathecal injection of 200 ng AVP or 10 microl anti-AVP serum and intravenous injection of 5 microg AVP or 200 microl anti-AVP serum did not influence the pain threshold. Pain stimulation reduced AVP concentration in hypothalamic paraventricular nucleus (PVN), and elevated AVP concentration in hypothalamic supraoptical nucleus (SON) and periaqueductal gray (PAG), but no change in AVP concentration was detected in pituitary, spinal cord and serum. The results indicated that AVP regulation of antinociception was limited to the brain nuclei.
Yang
Jun
J
Institute for Pharmaceuticals and Medical Science, Guangdong Bangmin Pharmaceutical Co. Ltd., Jianghai District, Jiangmen, Guangdong 529000, China. yj6676@yahoo.com
Song
Cao-You
CY
Liu
Wen-Yan
WY
Lin
Bao-Cheng
BC
D000818:Animals; D001127:Arginine Vasopressin / Q000502:physiology*; D008297:Male; D010146:Pain / Q000378:metabolism*; D010286:Paraventricular Hypothalamic Nucleus / Q000737:chemistry / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013495:Supraoptic Nucleus / Q000737:chemistry / Q000502:physiology*
D001127:Arginine Vasopressin