title: Inhibition of hematopoietic prostaglandin D synthase improves allergic nasal blockage in guinea pigs.
abstract: Although it has been suggested that prostaglandin (PG) D(2) is involved in the pathogenesis of allergic rhinitis, whether the inhibition of hematopoietic PGD(2) synthase (H-PGDS) shows beneficial effects on allergic rhinitis has been unclear. We evaluated the effects of a selective H-PGDS inhibitor, TFC-007, on nasal symptoms on Japanese cedar pollen-induced allergic rhinitis of guinea pigs. Sensitized animals were challenged with the pollen once a week. TFC-007 (30mg/kg, p.o.) given once before a challenge almost completely suppressed PGD(2) production in the nasal tissue early and late after the challenge. Although pre-treatment did not affect the incidences of sneezing and early phase nasal blockage, late phase nasal blockage was partially but significantly attenuated; however, nasal eosinophilia was not suppressed. In contrast, when TFC-007 was given once 1.5h after the challenge, the late phase response was not affected. Collectively, PGD(2) produced by H-PGDS early after an antigen challenge can participate in the induction of late phase nasal blockage, although the mechanism may be independent of eosinophil infilatration. The strategy for H-PGDS inhibition may be beneficial for allergic rhinitis therapy.
authors: Department of Pharmacology, Kyoto Pharmaceutical University, Nakauchi, Misasagi, Yamashina, Japan. nabe@mb.kyoto-phu.ac.jp
authors: Takeshi
authors: T
authors: Nabe
authors: Yusuke
authors: Y
authors: Kuriyama
authors: Nobuaki
authors: N
authors: Mizutani
authors: Saki
authors: S
authors: Shibayama
authors: Asami
authors: A
authors: Hiromoto
authors: Masanori
authors: M
authors: Fujii
authors: Katsunao
authors: K
authors: Tanaka
authors: Shigekatsu
authors: S
authors: Kohno