misoprostol and Hyperglycemia

Acute hyperglycemia evokes gastric slow wave dysrhythmias via endogenous prostaglandin generation. Ginger exhibits slow wave antiarrhythmic effects in other models, but its actions on hyperglycemia-evoked gastric dysrhythmias are unexplored. We hypothesized that ginger prevents disruption of slow wave rhythm by acute hyperglycemia via inhibition of prostaglandin production but not its actions. Twenty-two healthy humans underwent fasting electrogastrography during hyperglycemic clamping to 250 to 290 mg/dl after double-blind placebo or ginger root (1 g). Responses were compared with the prostaglandin E1 analog misoprostol (400 microg). Dominant frequencies (DF) and the percentage of recording times in the bradygastric [0.5-2 cycles/min (cpm)], normal (2-4 cpm), and tachygastric (4-9 cpm) frequency ranges were analyzed. After placebo, hyperglycemia reduced normal 2 to 4 cpm activity from 94.4 +/- 2.6 to 66.0 +/- 10.4%, increased the DF from 2.96 +/- 0.04 to 4.09 +/- 0.45 cpm, and increased tachygastria from 2.0 +/- 1.4 to 29.3 +/- 10.7% (P < 0.05). Hyperglycemia effects on normal activity (77.3 +/- 8.3%), DF (3.46 +/- 0.37 cpm), and tachygastria (15.6 +/- 8.6%) were significantly reduced by ginger (P < 0.05). Misoprostol evoked decreases in normal activity from 95.4 +/- 2.0 to 81.7 +/- 3.0% and increases in tachygastria from 3.1 +/- 1.6 to 11.2 +/- 2.4% (P < 0.05). However, ginger did not correct these abnormalities versus placebo (P = N.S.). In conclusion, acute hyperglycemia evokes gastric slow wave dysrhythmias that are prevented by ginger root. Conversely, the compound has no effect on dysrhythmias elicited by a prostaglandin E(1) analog, indicating that ginger likely acts to blunt production of prostaglandins rather than inhibiting their action. These findings suggest novel mechanisms for the traditional Chinese herbal remedy ginger.

Topics: Adult; Blood Glucose; Double-Blind Method; Electrophysiology; Female; Glucose Clamp Technique; Humans; Hyperglycemia; Male; Middle Aged; Misoprostol; Phytotherapy; Plant Extracts; Plant Roots; Prostaglandin Antagonists; Prostaglandins; Stomach Diseases; Zingiber officinale