Objective: We investigated the effects of various pH and glucose concentrat
ions on the growth of human peritoneal mesothelial cells and on coagulation
and fibrinolytic factors. Materials and methods. Cells were cultured at va
rious pH values in Ham's F-12 medium containing 1.0% foetal calf serum and
supplemented with D-glucose or D-mannitol at various concentrations. After
Ws h, cell proliferation and H-3-thymidine incorporation were determined. C
oagulation and fibrinolytic factors were measured after 48 h. Results: Gluc
ose caused concentration-dependent inhibition of cell growth at all pH valu
es, but the deleterious effect of low pH on cell proliferation was faster a
nd stronger than that of high glucose. At a similar osmolality, mannitol ca
used less inhibition of cell proliferation than glucose. There was a glucos
e concentration-dependent increase of thrombin-antithrombin III complex pro
duction at all pH values. At pH 5.2, tissue-type plasminogen activator prod
uction was far lower than at higher pH values, and production of the plasmi
nogen activator inhibitor showed a glucose concentration-dependent increase
. At pH 6.5 or 7.3, however, the plasminogen activator inhibitor production
decreased and tissue-type plasminogen activator production increased in a
glucose concentration-dependent manner. Conclusions. Low pH and/or high glu
cose culture medium had an inhibitory effect on peritoneal mesothelial cell
s, with the effect of high glucose being partially related to hyperosmolali
ty. These cells may modulate peritoneal coagulant and fibrinolytic activity
, with the balance between coagulation and fibrinolysis being disturbed by
low pH and/or high glucose.