Fig. 4
From: K2P2.1 channels modulate the pH- and mechanosensitivity of pancreatic stellate cells
The morphology and membrane potential of PSCs are regulated K2P2.1-dependently when challenged by altered pHe and ambient pressure. A K2P2.1+/+ and K2P2.1−/−. PSCs were cultured at the indicated pHe at ambient pressure for 48 h. Grey stripes indicate culture conditions in the presence of an elevated ambient pressure (+ 100 mmHg) (c, d, g, h). Cells were loaded with the fluorescent voltage-sensitive dye DiBAC4(3). (a) K2P2.1+/+ PSCs cultured at pHe 6.6 were small, consistent with their inactivated state [24]. (b) The size of K2P2.1+/+ PSCs increased when they were cultured at pHe 7.4. (c, d) Culturing K2P2.1−/− PSCs at ambient or elevated (+ 100 mmHg) pressure for 48 h resulted in an increased size independently of pHe. (e, f) K2p2.1.−/− PSCs had an increased size regardless of the ambient conditions. They responded neither to changes of pHe (e, f) nor to the application of pressure (g, h). B and C Summary of the morphometric analyses of PSCs cultured at ambient pressure (B) or at an elevated pressure (C). (N ≥ 3, n ≥ 30). D and E Summary of the membrane potential measurements under ambient pressure (D) and under elevated pressure (E). Application of pressure caused the membrane potential of PSCs to hyperpolarize in a partially K2P2.1-dependent way (N ≥ 3, n ≥ 30)