Figure 5
From: Central dopamine D2 receptors regulate plasma glucose levels in mice through autonomic nerves
Role of sympathetic and parasympathetic nerves in hyperglycemia induced by the dopamine D2 receptor agonist and antagonist. (a, b) Effect of the β2 adrenoceptor antagonist ICI 118,551 on hyperglycemia induced by quinpirole or l-sulpiride. ICI 118,551 (2 mg/kg, i.p.) was administered 30 min before injection of quinpirole (10 μg, i.c.v.; a) or l-sulpiride (10 μg, i.c.v.; b). Each point represents the mean ± S.E.M. of 8–15 mice. *P < 0.05, **P < 0.01, ***P < 0.001 vs. vehicle-vehicle group. +P < 0.05, +++P < 0.001 vs. ICI 118,551-vehicle group. ###P < 0.001 vs. vehicle-l-sulpiride group. (c, d) Effect of hepatic vagotomy on hyperglycemia induced by quinpirole (10 μg, i.c.v.; c) and l-sulpiride (10 μg, i.c.v.; d). Hepatic vagotomy was conducted at least 1 week before drug injections. Each point represents the mean ± S.E.M. of 7–12 mice. *P < 0.05, **P < 0.01, ***P < 0.001 vs. sham-vehicle group. +P < 0.05, ++P < 0.01, +++P < 0.001 vs. vagotomy-vehicle group. #P < 0.05, ##P < 0.01, ###P < 0.001 vs. sham-quinpirole group.
