ABSTRACT
Objective Platelet activating factor(PAF),which has been implicated in the pathophysiology of inflammation in asthma,is degraded and inactivated by PAF acetlhydrolase(PAF AH).To investigate the association of PAF AH activity with genotype in asthmatic children.Methods We studied 57 asthmatic children and 30 normal controls. The plasma PAF AH genotype was detected as representative case with 3 different genotypes (Val/Val,Val/Phe and Phe/Phe) by allele specific polymerase chain reaction(AS PCR).The PAF AH activity in plasam was examined by the changes of substrate assay.Results In severe asthmatic individuals plasma PAF AH activities were lower than those of mild or moderate groups and control group,and plasma PAF AH activition was absent 15.4 %.In another three groups plasma PAF AH activation were absent 2 %-3 %.There was significant difference of plasma PAF AH activity among 3 groups of genotype(Val/Val,Val/Phe and Phe/Phe).In the similar genotype, there was no significant difference of plasma PAF AH activity between the groups of control and asthma.Conclusions There was imbalace of PAF/PAF AH in asthmatic children. In severe asthmatic individuals plasma PAF AH activities were lower than those of mild or moderate groups and control group. PAF AH(Val279Phe) gene mutation was related with plasma PAF AH activity.