Potential excitatory role of nitric oxide on 2-deoxy-d-glucose-induced gastric motility in rats

Previous studies have shown that 2-deoxy-d-glucose (2-DG) increases gastric motility via the vagus nerve, but the underlying mechanism remains elusive. Since nitric oxide (NO) is involved in gastric motility, a possible interplay between 2-DG and NO can be suggested. In the present study, Wistar rats (250-350 g) of both sexes were intravenously injected with 2-DG (200 mg/kg), and the effects of the intravenous injection of the nitric oxide synthase (NOS) inhibitors; nitro-l-arginine methyl ester (l-NAME, 10 mg/kg) and N^ω -nitro-l-arginine (l-NNA, 10 mg/kg) were investigated. Animals were anaesthetized and cannulated for intravenous drug injections while the left vagal nerve was electrically stimulated (0.1-10 Hz, 0.5 ms duration, 12 V, for 60 seconds), and intragastric pressure and gastric motility changes were monitored using a latex gastric balloon. 2-DG increased the mean intragastric pressure (baseline, 5.0±0.4 cmH₂ O; after 2-DG, 14.4±1.5 cmH₂ O; P=.0156) and significantly increased the gastric motility index, while NOS inhibitors significantly attenuated both parameters. However, pretreatment with NOS inhibitors significantly augmented the gastric responses to peripheral electrical vagal stimulation. These results suggest that NO plays an excitatory role in gastric responsiveness to 2-DG and that this function may be effected in the central nervous system.