Rapid Gastric emptying in spontaneously hypertensive rats

Objective: To assess the rate of gastric emptying in spontaneously hypertensive rats (SHR) and to evaluate rapid gastric emptying as a possible predisposing factor for hypertension. Rapid gastric emptying of carbohydrates, known to elevate postprandial serum glucose, has been reported to occur in many insulinresistant states, including hypertension. SHR exhibit insulin resistance similar to human hypertensive patients. No prior studies have assessed gastric emptying of an oral glucose solution in SHR as compared with control Wistar Kyoto rats (WKY). Methods: Using scintigraphic imaging, gastric emptying of a physiologic, orally consumed glucose solution was assessed in 12 SHR and 12 control WKY at 5weeks of age, prior to the development of hypertension, and at 12 weeks of age after hypertension was fully established. Results: At 5 weeks, the gastric half-emptying time (GHET) was 67.8 +/- 9.8 min for the SHR vs. 109.3 +/- 18 (P = 0.042) minutes for the WKY controls. At 12 weeks, the GHET was 37.29 +/- 10.3 min for the SHR vs. 138.53 +/- 37.6 (P = 0.016) min for the WKY controls. Conclusion: :Gastric emptying was significantly more rapid in the SHR before and after the development of hypertension. Even though SHR are known to have increased sympathetic activity associated with their development of hypertension, this increased sympathetic activity does not inhibit gastric emptying. SHR are a promising animal model for investigating therapeutic agents for treating hypertension aimed at slowing the rate of gastric emptying.