Effect of alpha 2-adrenergic, cholinergic, and nonsteroidal anti-inflammatory drugs on myoelectric activity of ileum, cecum, and right ventral colon and on cecal emptying of radiolabeled markers in clinically normal ponies.
Abstract: To determine effect of xylazine hydrochloride (XYL), yohimbine hydrochloride (YOH), bethanechol chloride (BET), neostigmine methyl sulfate (NEO), or flunixin meglumine (FLU) on ileocecocolic myoelectric activity and passage of radiolabeled markers from the cecum. Methods: 6 healthy adult ponies. Methods: A cecal cannula was surgically implanted, and 12 were sutured to the ileum, cecum, and right ventral colon. After a 12-hour nonfeeding period, 370 MBq of technetium 99m-labeled sulfur colloid in egg albumen and 37 MBq of indium 111-labeled diethyltriaminepentaacetic acid in 60 ml of water were injected into the cecal apex. All drugs were administered i.v. as a bolus, with the exception of NEO, which was given SC: XYL, 0.5 mg/kg of body weight; YOH, 0.075 mg/kg; BET, 0.025 mg/kg; NEO, 0.025 mg/kg; FLU, 1.1 mg/kg; and saline solution (SAL), 10 ml. Drugs were administered in a randomized complete block design, each treatment was administered twice to each pony, and dual-phase scintigraphic images were obtained. The time to 50% emptying (t50) and the slope of the emptying curve (beta) were derived from the calculated power exponential equation. Results: The t50 after BET (184.8 +/- 16.5 minutes) and NEO (124.7 +/- 16.5 minutes) administration were significantly shorter than values after saline (230.2 +/- 17.1 minutes) administration. The t50 after XYL administration (250.5 +/- 18.6 minutes) was longer, and that after YOH administration (190.1 +/- 16.2 minutes) was shorter, than the t50 after saline administration, but neither difference was significant. The t50 and beta after FLU administration differed from those after saline administration. Myoelectric data appeared to be well correlated with drug-induced alterations in isotope clearance. Conclusions: Cholinergic agonists, BET and NEO, have significant effects on the myoelectric activity of ileum, cecum, and right ventral colon, with the net effect of hastening cecal emptying.
Publication Date: 1998-04-02 PubMed ID: 9522952
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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This study investigates how various drugs impact the electrical activity of different parts of the digestive system and the rate of cecal emptying in healthy ponies. The drugs tested include xylazine hydrochloride, yohimbine hydrochloride, bethanechol chloride, neostigmine methyl sulfate, and flunixin meglumine.
Research Methodology
- The study involved 6 adult ponies in good health. A cecal cannula was surgically inserted into each pony and 12 sutures were affixed to the ileum, cecum, and the right ventral colon.
- Following a 12-hour fasting period, the ponies were injected with radioactive markers 99m Technetium-labeled sulfur colloid and Indium 111-labeled diethyltriaminepentaacetic acid into the cecal apex. All the drugs were administered intravenously as a bolus, except for neostigmine methyl sulfate which was given subcutaneously.
- The researchers employed a randomized complete block design in the administration of the drugs. Each treatment was administered twice to each pony and dual-phase images were obtained using scintigraphy. The time taken to empty half the cecum and the emptying curve’s slope were calculated using a power exponential equation.
Major Findings
- The results showed that the time to 50% emptying (t50) was significantly shorter after administration of bethanechol chloride (184.8 +/- 16.5 minutes) and neostigmine methyl sulfate (124.7 +/- 16.5 minutes) in comparison to saline solution (230.2 +/- 17.1 minutes).
- Conversely, xylazine hydrochloride increased the t50 (250.5 +/- 18.6 minutes) while yohimbine hydrochloride decreased it (190.1 +/- 16.2 minutes), although neither change was deemed significant statistically.
- The beta and t50 after administration of flunixin meglumine also differed from those after saline administration.
- Data acquired from myoelectric readings correlated well with the alterations in isotope clearance induced by the drugs.
Conclusions
- The research concluded that cholinergic agonists, namely bethanechol chloride and neostigmine methyl sulfate, significantly affected the electrical activity in the ileum, cecum, and right ventral colon, resulting in hastened emptying of the cecum.
Cite This Article
APA
Lester GD, Merritt AM, Neuwirth L, Vetro-Widenhouse T, Steible C, Rice B.
(1998).
Effect of alpha 2-adrenergic, cholinergic, and nonsteroidal anti-inflammatory drugs on myoelectric activity of ileum, cecum, and right ventral colon and on cecal emptying of radiolabeled markers in clinically normal ponies.
Am J Vet Res, 59(3), 320-327.
Publication
Researcher Affiliations
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0125, USA.
MeSH Terms
- Adrenergic alpha-2 Receptor Agonists
- Adrenergic alpha-2 Receptor Antagonists
- Animals
- Anti-Inflammatory Agents, Non-Steroidal / pharmacology
- Bethanechol / pharmacology
- Cecum / diagnostic imaging
- Cecum / drug effects
- Cecum / physiology
- Clonixin / analogs & derivatives
- Clonixin / pharmacology
- Colon / diagnostic imaging
- Colon / drug effects
- Colon / physiology
- Electromyography / drug effects
- Electromyography / veterinary
- Gastrointestinal Motility / drug effects
- Horses / physiology
- Ileum / diagnostic imaging
- Ileum / drug effects
- Ileum / physiology
- Muscle, Smooth / diagnostic imaging
- Muscle, Smooth / drug effects
- Muscle, Smooth / physiology
- Neostigmine / pharmacology
- Pentetic Acid
- Radionuclide Imaging
- Radiopharmaceuticals
- Receptors, Adrenergic, alpha-2 / physiology
- Reference Values
- Technetium Tc 99m Sulfur Colloid
- Xylazine / pharmacology
- Yohimbine / pharmacology
Citations
This article has been cited 11 times.- Munsterman AS, Dias Moreira AS, Kottwitz J. Evaluation of the Effects of Detomidine on Equine Myoelectrical Activity Using Electrointestinography. J Vet Emerg Crit Care (San Antonio) 2025 Mar-Apr;35(2):120-130.
- Mushtaq S, Das YK, Aksoy A. Comparison of the Inhibitory Effects of Flunixin Meglumine and Meloxicam on the Smooth Muscles Motility of the Gastrointestinal Tract of Cattle. Vet Med Sci 2025 Jan;11(1):e70190.
- Verhaar N, Hoppe S, Grages AM, Hansen K, Neudeck S, Kästner S, Mazzuoli-Weber G. Dexmedetomidine Has Differential Effects on the Contractility of Equine Jejunal Smooth Muscle Layers In Vitro. Animals (Basel) 2023 Mar 10;13(6).
- Gough RL, McGovern KF, Bladon BM, Carmichael LA. Caecal dysfunction following standing surgical procedures. Vet Med Sci 2022 Sep;8(5):1930-1935.
- Abass M, Ibrahim H, Salci H, Hamed MA. Evaluation of the effect of different sedative doses of dexmedetomidine on the intestinal motility in clinically healthy donkeys (Equus asinus). BMC Vet Res 2022 Jul 14;18(1):274.
- Steinmann M, Bezugley RJ, Bond SL, Pomrantz JS, Léguillette R. A wireless endoscopy capsule suitable for imaging of the equine stomach and small intestine. J Vet Intern Med 2020 Jul;34(4):1622-1630.
- Tabar JJ, Cruz AM. Cecal rupture in foals--7 cases (1996-2006). Can Vet J 2009 Jan;50(1):65-70.
- El-Khodery SA, Sato M. Ultrasonographic assessment of the reticular motility in cows after administration of different doses of metoclopramide and neostigmine. Vet Res Commun 2008 Aug;32(6):473-80.
- Pfeiffer JB, Mevissen M, Steiner A, Portier CJ, Meylan M. In vitro effects of bethanechol on specimens of intestinal smooth muscle obtained from the duodenum and jejunum of healthy dairy cows. Am J Vet Res 2007 Mar;68(3):313-22.
- Koenig J, Cote N. Equine gastrointestinal motility--ileus and pharmacological modification. Can Vet J 2006 Jun;47(6):551-9.
- Mitchell CF, Malone ED, Sage AM, Niksich K. Evaluation of gastrointestinal activity patterns in healthy horses using B mode and Doppler ultrasonography. Can Vet J 2005 Feb;46(2):134-40.
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