Inhibition of MDCK cell cyst formation and expansion as a model of
polycystic kidney disease. A, MDCK cells were cultured in a collagen matrix
and exposed for 7 days to 1 μM forskolin (top) or 1 μM forskolin
together with 20 μM CNTinh-03 (bottom). Arrows point to
developing cysts. B, cysts growth rates. Growth rates determined for
individual cysts from cyst area at day 7 divided by initial cyst area at day 1
(Cyst areafinal/areainitial). Each closed circle
represents one cyst. C, left, percentage of MDCK cells that developed into
cysts. MDCK cells were treated for 7 days with forskolin (1 or 5 μM),
without or with 20 μM CNTinh-03. Data shown as mean ±
S.E. (n = 4 sets of cultures). Right, cAMP concentration in MDCK
cells incubated with indicated concentrations of forskolin, without or with 20
μM CNTinh-03 (SE, n = 4).