Sympathetic control of gastric motility.
Since the role and mode of action of the sympathetic nervous system on interdigestive gastric motility is still unclear, we studied the effects of alpha- and beta-adrenergic agents in 44 males without gastrointestinal diseases by 60 min i.v. infusion of the drugs. Each person had 2 experiments, with normal saline solution as a control and either of the drugs, applied in randomized order. The basic electrical rhythm (BER) and spike activity of the stomach were recorded by a probe with bipolar suction-needle electrodes placed in the antrum. The interdigestive migrating electrical complex (IDMEC) was recorded by a probe with 2 bipolar ring electrodes placed in the corpus and antrum of the stomach. The alpha-agonist norepinephrine, 0,4 micrograms/kg/min and the beta-agonist orciprenaline, 2 micrograms/kg/min, reduced the frequency of BER by 0.48 +/- 0.19 c/min and 0.68 +/- 0.10 c/min respectively, and decreased the spike activity by 22.7 +/- 3.1% and 30.8 +/- 2.3% respectively. Norepinephrine shortened the duration of phase III from 5.1 +/- 1.9 min to 3.0 +/- 1.4 min, and orciprenaline from 4.7 +/- 1.1 min to 2.2 +/- 0.5 min. The alpha-antagonist phentolamine, 50 micrograms/kg/min and the beta-agonist propranolol, 10 micrograms/kg/min, increased the BER frequency by 0.88 +/- 0.10 c/min and 0.64 +/- 0.13 c/min respectively. They increased the spike activity by 20.7 +/- 2.4% and 58.3 +/- 2.0% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)