Isoform-specific regulation of mood behavior and pancreatic β cell and cardiovascular function by L-type Ca²⁺ channels
J. Clin. Invest. Martina J. Sinnegger-Brauns, et al. 113:1430 doi:10.1172/JCI20208 [Go to this article.]

Figure 4
DHP sensitivity of L-type I_Ca and insulin secretion in isolated pancreatic β cells. (A) Whole-cell I_{Ca, L} during 100-ms depolarizations from –70 mV to 0 mV in single pancreatic β cells isolated from WT and Ca_v1.2DHP–/– mice. The L-type channel activator BayK (2 μM) or the L-type channel inhibitor isradipine (2 μM) were added as indicated. (B) Charge-voltage (Q-V) relations recorded in β cells (100-ms depolarizations to voltages between –60 mV and +20 mV) from WT and Ca_v1.2DHP–/– mice in the absence (open circles) or presence of BayK (filled diamonds) or isradipine (filled circles). Data represent mean ± SEM (n = 4–5). In WT β cells the effects of isradipine and BayK were significant (P < 0.05; Student t test) at depolarizations beyond –30 mV and –10 mV, respectively. (C) Insulin secretion measured in isolated islets from control (black bars) and Ca_v1.2DHP–/– (white bars) mice in the absence and presence of glucose and DHPs as indicated. Data are mean ± SEM (n = 6). ***P < 0.001 (Student t test) for isradipine inhibition; *P < 0.05 for BayK stimulation (WT vs. Ca_v1.2DHP–/–).