title: PAF responsiveness in Japanese subjects with plasma PAF acetylhydrolase deficiency.
abstract: Approximately 4% of the Japanese population genetically lack plasma platelet activating factor acetylhydrolase (PAF-AH) and show a higher prevalence of thromboembolic disease, but whether they are susceptible to another PAF-related disease, asthma, remains controversial. To determine the role of plasma PAF-AH in airway physiology, we performed PAF bronchoprovocation tests in 8 plasma PAF-AH-deficient subjects and 16 control subjects. Serial inhalation of PAF (1-1000 microg/ml) concentration-dependently induced acute bronchoconstriction, but there was no significant difference between PAF-AH-deficient and control subjects (11.7 +/- 4.6% vs. 9.6 +/- 2.8% decrease in forced expiratory volume in 1 s). Transient neutropenia after single inhalation of PAF (1000 microg/ml) showed no significant difference between the groups either in its magnitude (72 +/- 11% vs. 65 +/- 9% decrease) or duration (4.1 +/- 1.0 vs. 3.3 +/- 0.8 min). In conclusion, a lack of plasma PAF-AH activity alone does not augment physiological responses to PAF in the airway.
authors.affiliation: Department of Medicine, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Naoki
authors.forename: Koichiro
authors.initials: K
authors.lastname: Asano
authors.forename: Nagato
authors.initials: N
authors.lastname: Satoh
authors.forename: Kouichi
authors.initials: K
authors.lastname: Fukunaga
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Oguma
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shiomi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakajima
authors.forename: Kyoko
authors.initials: K
authors.lastname: Niimi
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Shiraishi
authors.forename: Akitoshi
authors.initials: A
authors.lastname: Ishizaka
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000097:blood / Q000172:deficiency* / Q000235:genetics; D000280:Administration, Inhalation; D000328:Adult; D000483:Alleles; D001249:Asthma / Q000201:enzymology / Q000453:epidemiology; D016084:Bronchoconstriction / Q000187:drug effects* / Q000502:physiology*; D005260:Female; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007700:Kinetics; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009503:Neutropenia / Q000139:chemically induced / Q000378:metabolism; D010972:Platelet Activating Factor / Q000008:administration & dosage / Q000009:adverse effects*; D012129:Respiratory Function Tests / Q000379:methods
chemical_list: D010972:Platelet Activating Factor; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase