PLASMA AND URINARY PLATELET-ACTIVATING-FACTOR CONCENTRATIONS AND LEUKOTRIENE RELEASING ACTIVITY OF LEUKOCYTES IN STEROID SENSITIVE NEPHROTIC SYNDROME OF CHILDHOOD
A. Huseyinov et al., PLASMA AND URINARY PLATELET-ACTIVATING-FACTOR CONCENTRATIONS AND LEUKOTRIENE RELEASING ACTIVITY OF LEUKOCYTES IN STEROID SENSITIVE NEPHROTIC SYNDROME OF CHILDHOOD, Acta Paediatrica Japonica Overseas Edition, 40(1), 1998, pp. 57-62
Platelet activating factor (PAF) is synthesized and secreted by glomer
ular mesangial and endothelial cells. It increases glomerular basement
membrane permeability and induces proteinuria. Leukotrienes (LT) are
mediators released by either leukocytes or glomerular cells under the
PAF effect. The possible role of PAF in steroid sensitive nephrotic sy
ndrome (SSNS) of childhood was studied in 8 children with SSNS in the
acute stage, 5 children in remission and 8 healthy controls. The PAF c
oncentrations in urine and plasma were determined. Leukocytes were sti
mulated in vitro and the LT release in response to stimulation was det
ermined. The urinary and plasma concentrations of PAF were significant
ly higher in the acute phase than in remission and in control patients
. Children with SSNS were found to have peripheral leukocytes with inc
reased LT releasing activity in vitro. These results are in accordance
with clinical and experimental observations indicating that PAF origi
nates in the kidney and plays a role in normal kidney physiology. Urin
ary PAF concentrations may be related to proteinuria because they were
strongly correlated in the present study. Elevated plasma PAF concent
rations in the acute stage of SSNS could result from either its secret
ion from the circulating leukocytes or decreased acetyl hidrolase acti
vity needed for its hydrolysis in plasma. The increased LT release in
vitro suggests that these cells might have been activated by PAF secre
ted from glomeruli. It is proposed that PAF and different LT in system
ic and glomerular circulation are important mediators in childhood SSN
S.