Table 1.

Effects of Ca2+ channel blockers on glucagon release

Condition	1 mM glucose	1mM glucose + 10 μM forskolin
Control	34.0 ± 2.6 (12)	100.5 ± 6.6 (12) *
1μM ω-conotoxin	18.8 ± 1.9 (10) *	92.1 ± 7.5 (10)
50 μM nifedipine	36.9 ± 4.1 (10)	55.5 ± 4.9 (10)†

Glucagon release (pg islet⁻¹ h⁻¹) was measured following 1 h incubations in the presence of 1 mM glucose alone (left column) or following activation of adenylate cyclase with 10 μM forskolin (right column) in the presence of the L- and N-type Ca²⁺ channel blockers nifedipine and ω-conotoxin. Data are means ± S.E.M. of the indicated number of experiments (in parentheses).

^*P < 0.001vs. Control (1 mM glucose alone)

^†P < 0.001vs. glucagon release measured in 1 mM glucose + 10 μM forskolin.