ABSTRACT
Objective To study the changes of phosphatidylcholine-specific phospholipase D (PC-PLD) enzyme activity of glomerular mesangial cells (GMCs) in high glucose and the effect of PLD on cytoskeleton. Methods Rats GMCs were cultured in high glucose(30 mmol/L) for 48 hours. PLD enzyme activity was measured by enzyme coupled colorimetry. PKC activity was measured by substrate phosphorylation, and fluorescence intensity of F-actin was observed by FITC-labeled antibody and laser scan cofocal microscopy (LSCM) . Results In high glucose, PLD and PKC activities were obviously elevated, but fluorescence intensity of F-actin was decreased and its cytoskeletal pattern was disassembly. After treatment with inhibtor of PLD, PKC activity was significantly decreased, and intensity and organization of F-actin were recovered. Conclusion Elevation of PLD activity induced by high glucose may influence the cytoskeleton and contraction of CMC through PKC pathway.
ABSTRACT
Objective To elucidate functional alterations of glomerular mesangial cell (GMC) contraction and its relationship with diabetic glomerular hyperfiltration. Methods Male Wistar rats were divided into groups of normal control and 2 weeks diabetes induced by STZ. GMC were cultured in the presence of normal glucose (5mM). Meanwhile in comparison GMC obstained from normal rats were cultured in the presence of 30 mM glucose for 48 h in vitro. By using laser scanning confocal microscopy (LSCM) , we measured basal calcium concentration, the changes of calcium level in response to vasoconstrictor agonist angiotensin H (Ang I ),and the effect of protein kinase C (PKC) inhibitor PMAC10 M,24 h)on cytosol calcium of GMCs. Results The creatinine clearance rate (Ccr) was increased with age in diabetic rats, reaching a peak at 2 weeks (P