Arginine vasopressin is an important regulator in antinociceptive modulation of hypothalamic paraventricular nucleus in the rat.
Our previous study has proven that hypothalamic paraventricular nucleus (PVN) stimulation increases pain threshold and PVN cauterization decreases pain threshold. The studied neuropeptides in PVN were investigated to involve to pain modulation in the rat. The results showed that (1) intraventricular injection (icv) of anti-arginine vasopressin (AVP) serum completely reversed pain threshold increase induced by l-glutamate sodium (Glu) injection into the PVN, and local administration (icv) of anti-leucine-enkephalin (L-Ek) serum or anti-beta-endorphin (beta-Ep) serum partly attenuated pain threshold increase induced by Glu injection into the PVN, but pre-treatment of anti-oxytocin (OXT), dynorphinA(1-13) (DynA(1-13)), cholecystokinin-like peptide (CCK), neurotensin (NT), corticotrophin-releasing hormone (CRH), adrenocorticotrophin (ACTH), somatostatin (SST), prolactin-releasing hormone (PRH), angiotensinII (AngII), vasoactive intestinal polypeptide (VIP), melanotropin-releasing hormone (MRH), thyrotropin-releasing hormone (TRH), substance P (SP) or growth hormone-releasing hormone (GHRH) serum (icv) did not influence the analgesic effect of PVN administration with Glu; (2) PVN stimulation with Glu elevated the concentrations of AVP, OXT, CCK, NT, CRH, SST, PRH and DynA(1-13) in PVN perfusion liquid, and could not change the concentrations of L-Ek, beta-Ep, AngII, ACTH, VIP, MRH, TRH, SP and GHRH in PVN perfusion liquid; (3) Pain stimulation increased the concentrations of AVP, L-Ek, beta-Ep, DynA(1-13), CRH and ACTH in PVN perfusion liquid, and did not alter the concentrations of OXT, CCK, NT, SST, PRH, AngII, VIP, MRH, TRH, SP and GHRH in PVN perfusion liquid. The data suggested that AVP played a more important role than the other studied peptides (OXT, L-Ek, beta-Ep, DynA(1-13), CCK, NT, CRH, ACTH, SST, PRH, AngII, VIP, MRH, TRH, SP and GHRH) in PVN antinociceptive progress.
Yang
Jun
J
Institute for Pharmaceuticals and Medical Science, Guangdong Bangmin Pharmaceutical Co. Ltd., Jianghai Distract, Jiangmen, Guangdong 529080, China. yj6676@yahoo.com
Yang
Yu
Y
Chen
Jian-min
JM
Xu
Hong-tao
HT
Liu
Wen-yan
WY
Wang
Cheng-hai
CH
Lin
Bao-cheng
BC
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D001127:Arginine Vasopressin / Q000502:physiology*; D004558:Electric Stimulation; D007276:Injections, Intraventricular; D008297:Male; D008845:Microinjections; D009479:Neuropeptides / Q000502:physiology*; D010147:Pain Measurement / Q000187:drug effects; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000502:physiology*; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley
D000700:Analgesics; D009479:Neuropeptides; D001127:Arginine Vasopressin