Yohimbine ameliorates the effects of endotoxin on gastric emptying of the liquid marker acetaminophen in horses.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research studied how yohimbine, a substance typically used for the treatment of sexual dysfunction, could help counteract the negative effects of certain bacterial toxins on the gastric emptying process in horses, using acetaminophen as a liquid marker.
Objective and Treatment Groups
The primary purpose of the study was to establish how the application of yohimbine impacted the gastric emptying of acetaminophen, a drug famously known for its pain relieving and fever reducing effects. The test was conducted on different groups of horses:
- Normal, fasted horses
- Horses administered with endotoxin derived from E. coli 055 B5
- Horses treated with yohimbine and the same endotoxin
These specific groupings allowed the researchers to observe the differences in gastric emptying between a normal state, a toxin-induced state, and when a potential counteracting agent (yohimbine) was introduced.
Administration of Substance and Marker
In the case of the horses given endotoxin, they were given a dose of 0.2 micrograms per kilogram of weight, intravenously. For the group treated with both yohimbine and endotoxin, the dosage was 0.25 mg/kg IV over a half an hour period. Then, acetaminophen was given via stomach tube, 15 minutes after the endotoxin infusion.
Quantification of Gastric Emptying
To quantify gastric emptying, the researchers collected blood samples for acetaminophen analysis. This enabled them to ascertain the timeline it took to reach peak serum concentration (Tmax), the maximum concentration obtainable (Cmax), and the total area under the acetaminophen serum concentration versus time curve (AUC) for each group.
Results
The study found that administration of endotoxin led to a significant increase in Tmax, demonstrating a noticeable delay in gastric emptying. However, this effect was significantly curbed (P < or = 0.05) with the introduction of yohimbine treatment. This suggests that yohimbine has a mitigating effect on the way endotoxins slow down the gastric emptying process.
Cite This Article
Publication
Researcher Affiliations
- Department of Large Animal Clinical Sciences, The University of Tennessee, College of Veterinary Medicine, Knoxville, 37901-1071, USA.
MeSH Terms
- Acetaminophen / pharmacokinetics
- Adrenergic alpha-Antagonists / pharmacokinetics
- Adrenergic alpha-Antagonists / pharmacology
- Animals
- Anti-Inflammatory Agents, Non-Steroidal / pharmacokinetics
- Area Under Curve
- Drug Interactions
- Endotoxins / pharmacology
- Female
- Gastric Emptying / drug effects
- Horses / physiology
- Yohimbine / pharmacokinetics
- Yohimbine / pharmacology
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Citations
This article has been cited 1 times.- Leung FW, Chan CC. Involvement of alpha(2)-adrenoceptors in the gastric protective effect of nitroglycerin against acidified ethanol-induced mucosal injury.. Dig Dis Sci 2007 Nov;52(11):3070-4.