Journal Article

Angiotensin II requires PDGF-BB to induce DNA synthesis in rat mesangial cells cultured in an exogenous insulin-free medium.

S Higueruelo and R Romero

in Nephrology Dialysis Transplantation

Volume 12, issue 4, pages 694-700
Published in print April 1997 | ISSN: 0931-0509
Published online April 1997 | e-ISSN: 1460-2385 | DOI: http://dx.doi.org/10.1093/ndt/12.4.694
Angiotensin II requires PDGF-BB to induce DNA synthesis in rat mesangial cells cultured in an exogenous insulin-free medium.

Show Summary Details

Preview

BACKGROUND: Mesangial cell proliferation is an important feature of chronic glomerular disease. Different cytokines and vasoactive substances have been implicated in mesangial cell proliferation. However, the role of angiotensin II remains controversial. Furthermore, all the studies made to date have been performed using a medium supplemented with high concentrations of insulin (5 micrograms/ml) in order to facilitate mesangial cell proliferation in vitro. As has recently been reported, insulin causes a change both in extracellular matrix composition and in mesangial cell phenotype, thus mimicking disease conditions. METHODS: We examined the effects of Ang II in synchronized and proliferating mesangial cells with and without growth factor (PDGF-BB, bFGF and/or insulin) supplementation and the effects of exogenous administration of insulin on mesangial proliferation by measuring the bromodeoxyuridine (BrdU) uptake. RESULTS: Angiotensin II itself caused no increase in BrdU incorporation. However, it exerted a significant synergistic effect on PDGF-BB-induced DNA synthesis (P < 0.05) in quiescent medium and tended to stimulate BrdU uptake by proliferating cells (P = 0.09). BrdU incorporation significantly correlated with direct cell count (r = 0.95). PDGF-BB had the maximal stimulatory effect on DNA synthesis both in quiescent and in proliferative culture conditions. The insulin dose (5 micrograms/ml) which has been shown to cause mesangial cell proliferation in vitro, caused an increase in BrdU incorporation by itself in quiescent medium. CONCLUSIONS: We conclude that in an insulin-free medium, mimicking in vivo glomerular conditions, PDGF-BB or proliferative medium are needed to allow Ang II-induced DNA synthesis in mesangial cell culture.

Journal Article.  0 words. 

Subjects: Nephrology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.