RT Journal Article
SR Electronic
T1 Changes in bronchial responsiveness, circulating leucocytes and ex vivo cytokine production by blood monocytes after PAF inhalation in allergic asthmatics
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 611
OP 618
DO 10.1183/09031936.95.08040611
VO 8
IS 4
A1 R Louis
A1 D Degroote
A1 T Bury
A1 JL Corhay
A1 JM Kayembe
A1 P Franchimont
A1 MF Radermecker
YR 1995
UL http://erj.ersjournals.com/content/8/4/611.abstract
AB We investigated the effects of inhaled platelet-activating factor (PAF) on methacholine bronchial responsiveness, circulating leucocyte counts, and ex vivo tumour necrosis factor alpha (TNF alpha) and interleukin-1 (IL-1) production from blood monocytes in eight allergic asthmatics. Bronchial responsiveness was defined as the provocative concentration of methacholine causing a 20% decrease in forced expiratory volume in one second (PC20). Circulating leucocytes were counted by means of an automatic haemocytometer, and cytokines were measured with specific immunoassays. The different variables were measured before and 4, 24, 48, 72 and 168 h after a PAF (225 micrograms), a lyso-PAF (225 micrograms) and a saline bronchial challenge. When compared with lyso-PAF and saline, inhalation of PAF resulted in a significant decrease in PC20 over a period of one week. Two falls in bronchial responsiveness were identified, the first by 4 h and the second beginning 48 h and reaching a maximum by 168 h. The increases in spontaneous TNF alpha and IL-1 production which occurred during the week after both PAF, lyso-PAF and saline, did not differ significantly. Likewise, the changes in circulating neutrophil counts, characterized by a transient rise by 4 h after PAF and lyso-PAF but not saline, followed by a fall by 24 h and a persistent decrease until 168 h, were not significantly different after PAF, lyso-PAF and saline. On the other hand, in comparison with lyso-PAF and saline, inhaled PAF caused a significant protracted augmentation in circulating eosinophil counts, which was maximal by 48 h but did not correlate with the delayed decline in PC20.(ABSTRACT TRUNCATED AT 250 WORDS)