Yoshihide Tatsumi (1), Masamichi Tanino (1), Tadashi Kodama (1), Kei
Kashima (1), Masashi Katsura (2) and Seitaro Okuma (2)
(1) Third Department of Internal Medicine, Kyoto Prefectural University
of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-0841, Japan
(2) Department of Pharmacology, Kawasaki Medical School, 577 Matsushima,
Kurashiki 701-0192, Japan
Abstract: Irsogladine maleate (IM) has been used as a mucosal
protective agent, whose action is partially explained as enhancement of
mucosal blood flow, increase of cellular cyclic AMP and facilitation of
gap-junctional intercellular communication. Effect of IM on rat gastric
mucosal hydrophobicity, one of the mucosal barrier properties, was investigated,
in comparison with that of 16,16-dimethyl prostaglandin E2 (dmPGE2).
IM alone had no effect on mucosal hydrophobicity and mucosal phospholipids
content. dmPGE2 alone did not change mucosal hydrophobicity significantly,
but remarkably increased mucosal surface-active phospholipids. Intragastric
administration of absolute ethanol significantly decreased gastric mucosal
hydrophobicity and mucosal phospholipids content. IM could prevent the decrease
in mucosal hydrophobicity by ethanol, maintaining the surface mucus gel
layer and mucosal surface phospholipids almost as non-damaged control levels,
whereas dmPGE2 also prevented the decrease in mucosal hydrophobicity
by ethanol, with the surface epithelium being partially exfoliated and mucosal
surface-active phospholipids showing remarkable enhancement. These results
suggest that IM may preserve gastric mucosal hydrophobicity against ethanol,
not through enhancement of mucosal phospholipids content like prostaglandin,
but possibly through its reported stabilization action to the epithelial
cell lining, which may preserve the surface epithelium with the mucous gel
layer containing surface-active phospholipids, a possible origin of mucosal
hydrophobicity.
Keywords: Mucosal hydrophobicity, Phospholipid, Irsogladine maleate