Effect of selective gastric intrinsic denervation on gastric motility in turkeys

The effect of selectively denervating portions of the myenteric plexus on g astroduodenal (GD) motility was examined in domestic turkeys (Meleagris gal lopavo). The neural network beneath the lateral or medial side of the isthm us between the glandular stomach and the muscular stomach was denervated by application of 1% benzalkonium chloride (BC). Image intensification radiol ogy (IIR) was performed postsurgically on the research subjects to observe GD contractions and to analyze aberrations. Two trials were performed. The first employed temporal controls by checking GD motility in all treated bir ds before and after BC had taken effect. The second trial controlled for th e trauma associated with the surgical procedure by applying 0.9% saline sol ution in lieu of BC in four turkeys. The normal GD contractions sequence as confirmed by these controls was thin muscle contraction, duodenal contract ion and outflow, thick muscle contraction, and, finally, glandular stomach contraction. Ablation of the nerves beneath the medial or lateral side of t he isthmus resulted in the same abnormality in GD motility, namely a lack o f thick muscle contractions. These results indicate that the entire myenter ic plexus associated with the isthmus must remain intact for proper GD moti lity to take place. Furthermore, it can be inferred that initiation and reg ulation of the thick muscle pair acts via nerves encircling the isthmus. Se condary regulatory mechanisms controlling GD motility may exist and should be tested through future investigation.