These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Nipradilol displays a unique pharmacological profile of affinities for the different alpha 1-adrenoceptor subtypes. Author: Kinami J, Tsuchihashi H, Maruyama K, Sasaki K, Nagatomo T. Journal: Jpn J Pharmacol; 1993 Feb; 61(2):81-6. PubMed ID: 7681491. Abstract: The selectivity of antagonistic effects of nipradilol, its four isomers and denitronipradilol, a major metabolite of nipradilol, on alpha 1-adrenoceptor subtypes in rat heart, brain and spleen were examined by radioligand binding assay with [3H]-prazosin. Pharmacological characteristics of these compounds were determined in isolated aortae from rats and guinea pigs. The order of the pKi values for alpha 1High-affinity sites in the heart, spleen and brain was SR > nipradiolol > or = RR > or = SS-RS >> denitronipradilol, but the order of the pKi values for the alpha 1Low-affinity sites was different in the heart and brain. There were good correlations between the pKi values of these compounds for the alpha 1High-affinity sites and the pA2 values for the contractile inhibition of the phenylephrine-induced response in rat aorta. There was no correlation between the pKi values of these compounds for the alpha 1Low-affinity sites and the pA2 values. These results indicate that: 1) alpha 1High-Affinity sites are related to vasoconstriction mediated by alpha 1-adrenoceptors; 2) Nipradilol and its isomers possess low affinity to alpha 1-adrenoceptors; and 3) The nitroxy group in nipradilol is important for its alpha 1-blocking activity.[Abstract] [Full Text] [Related] [New Search]