Prokinetic effects of erythromycin on the ileum, cecum, and pelvic flexure of horses during the postoperative period.
OBJECTIVE
To evaluate the effect of erythromycin on motility of the ileum, cecum, and pelvic flexure of horses during the postoperative and post-recovery periods.


METHODS
8 healthy adult horses.


METHODS
Horses were anesthetized and bipolar electrodes were implanted in smooth muscle of the ileum, cecum, and pelvic flexure. Approximately 4, 16, and 24 hours (postoperative recording sessions) and at least 8 days (post-recovery recording session) after surgery, myoelectric activity was recorded before and after administration of erythromycin (0.5 mg/kg).


RESULTS
Following erythromycin administration, myoelectric activity was increased in the ileum during all postoperative recording sessions but not during the post-recovery recording session. Myoelectric activity was increased in the cecum following erythromycin administration only during the post-recovery recording session. Myoelectric activity was increased in the pelvic flexure following erythromycin administration during all recording sessions. During several recording sessions, there were short periods during which myoelectric activity was significantly decreased following erythromycin administration.


CONCLUSIONS
Results suggest that erythromycin has an effect on myoelectric activity of the ileum, cecum, and pelvic flexure in horses; however, prokinetic effects of erythromycin administered during the postoperative period were not always the same as effects obtained when the drug was administered after horses had recovered from the effects of surgical implantation of recording devices. Therefore, caution must be exercised when extrapolating results of prokinetic studies in healthy animals to animals with abnormal gastrointestinal tract motility.
Roussel
A J
AJ
Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, Texas A&M University, College Station 77843-4475, USA.
Hooper
R N
RN
Cohen
N D
ND
Bye
A D
AD
Hicks
R J
RJ
Bohl
T W
TW
D000818:Animals; D002432:Cecum / Q000187:drug effects*; D004917:Erythromycin / Q000494:pharmacology*; D005765:Gastrointestinal Agents / Q000494:pharmacology*; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006736:Horses / Q000601:surgery*; D007082:Ileum / Q000187:drug effects*; D016065:Myoelectric Complex, Migrating / Q000187:drug effects; D010388:Pelvis; D011184:Postoperative Period
D005765:Gastrointestinal Agents; D004917:Erythromycin