DIFFERENCE IN SERUM-INDUCED PROSTACYCLIN PRODUCTION BY CULTURED AORTIC AND CAPILLARY ENDOTHELIAL-CELLS

Prostacyclin (PGI,) generated by vascular endothelial cells plays an i mportant role in the maintenance of vessel wall homeostasis. Human pla sma-derived serum (PDS) stimulated PGI, synthesis by both cultured bov ine aortic endothelial cells (BAEC) and adrenal capillary endothelial cells (BCEC), but the PGI(2) response of the latter cells was far smal ler, When BAEC were cultured with a high concentration of glucose (400 mg/dl), the PGI(2) synthesis induced by 20% PDS was significantly low er than that in the culture with a physiological concentration of gluc ose (100 mg/dl) (258 +/- 45 pg/10(4) cells/h vs. 402 +/- 52 pg/10(4) c ells/h, n = 4, P < 0.05). On the other hand, there was no significant difference in the PDS-induced PGI, synthesis between BCEC cultured wit h high and physiological concentrations of glucose. Additionally, 10% PDS obtained from patients with non-insulin dependent diabetes mellitu s (n = 6) stimulated significantly less PGI, synthesis than that from healthy subjects (n = 4) in the case of both BAEC (133 +/- 27 pg/l0(4) cells/h vs. 402 +/- 38 pg/l0(4) cells/h, P < 0.05) and BGEC (72 +/- 1 5 pg/l0(4) cells/h vs. 118 +/- 12 pg/l0(4) cells/h, P < 0.05), with th e difference in PGI, synthesis being smaller for BCEC. These findings indicate that the PDS-induced PGI, synthesis differs between cultured vascular endothelial cells from large and small vessels with the decre ase in PGI, synthesis by diabetic PDS and high glucose being more mark ed for BAEC than BCEC.