Figure 2.

The effects of JV-1–36 (300 nM) (A) and JV-1–53 (100 nM) (B) on basal and VIP-induced cAMP efflux from rat pineal cells in a superfusion system. After two 6-min infusions of 10 nM VIP (solid filled bars), the cells were exposed to JV-1–36 or JV-1–53 for 9 min (checkered bars) followed by a simultaneous infusion of these analogs and 10 nM VIP for an additional 6 min (filled bars) (0-min inhibition). The duration of the inhibitory effect of these analogs was evaluated by a 6-min infusion of 10 nM VIP in 60 min (filled bars) (60-min inhibition). The second VIP-induced cAMP response, before the antagonist exposure was used as reference value.