Open AccessCerebrovascular Effects of the TRH Analogues pGlu-3-methyl-His-Pro Amide and pGlu-Glu-Pro Amide: A Comparison with TRH
Author(s) -
LarsOwe D. Koskinen,
Mona Koch,
Jan Svedberg
Publication year - 2000
Publication title -
upsala journal of medical sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.808
H-Index - 41
eISSN - 2000-1967
pISSN - 0300-9734
DOI - 10.1517/03009734000000049
Subject(s) - amide , medicine , thyrotropin releasing hormone , endocrinology , cerebral blood flow , hormone , neuropeptide , blood flow , chemistry , biochemistry , receptor
The goal of the study was to assess whether TRH analogues possess cerebrovascular effects similar to the native peptide. The neuropeptide thyrotropin releasing hormone (TRH) elicits cerebrovasodilation in several species under various conditions. The laser-Doppler method was employed to study the effects of TRH and the analogues pGlu-3-methyl-His-Pro amid (M-TRH) and pGlu-Glu-Pro amide. Intravenous (i.v.) injection of 300 microg kg(-1) of TRH elicited cerebrovasodilation and a 62% increase in blood flow within 1 minute. M-TRH, in a dose of 300 microg kg(-1) i.v., elicited a 80% increase in cerebral blood flow. Even a minute dose of M-TRH (625 ng kg(-1)) caused an increase in cerebral blood flow. No clear difference in effects on the cerebral blood flow was observed between spontaneously and mechanically ventilated animals, pGlu-Glu-Pro amide had no cerebrovascular effect.