Back to Search Start Over

Long-lasting binding of IT-066 to human histamine H2 receptor.

Authors :
Otsuka, Hiroko
Fukushima, Yasushi
Tamai, Michiko
Takahashi, Haruki
Mori, Haruki
Asano, Tomoichiro
Katsube, Takao
Ogawa, Kenji
Kajiwara, Tetsuro
Ohkawa, Sin-ichiro
Saitoh, Toshihito
Otsuka, H
Fukushima, Y
Tamai, M
Takahashi, H
Mori, H
Asano, T
Katsube, T
Ogawa, K
Kajiwara, T
Source :
Digestive Diseases & Sciences; Apr2000, Vol. 45 Issue 4, p796-801, 6p
Publication Year :
2000

Abstract

Based on animal models, IT-066, a histamine H2-receptor antagonist, is reported to possess potent and long-lasting antagonisms on histamine H2 receptor (H2R) -mediated effects. However, no reports have been published concerning its interaction with the human H2R. The aim of this study is to characterize its interaction with human H2R. Chinese hamster ovary cell lines stably expressing human H2Rs were obtained. The effects of IT-066, famotidine, and ranitidine on tiotidine binding and histamine-stimulated cAMP production were analyzed. IT-066 inhibited [3H]tiotidine binding and histamine-stimulated cAMP production more potently than famotidine or ranitidine. In addition, preincubation with 10(-5) M IT-066, but not with 10(-5) M famotidine or 10(-4) M ranitidine, had marked inhibitory effects long after extensive washing. Paraformaldehyde fixation of the cells blunted inhibition of [3H]tiotidine binding induced by preincubation with IT-066, but not that by preincubation with famotidine or ranitidine. IT-066 has potent and long-lasting antagonisms on human H2R. At least one of the IT-066 binding sites is not shared by famotidine, ranitidine, or tiotidine and is affected by paraformaldehyde fixation. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
01632116
Volume :
45
Issue :
4
Database :
Complementary Index
Journal :
Digestive Diseases & Sciences
Publication Type :
Academic Journal
Accession number :
49834718
Full Text :
https://doi.org/10.1023/A:1005464231214