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Updated: Aug 14, 2025

Fabrication and Implantation of Miniature Dual-element Strain Gages for Measuring In Vivo Gastrointestinal Contractions in Rodents.
Published on: September 18, 2014
Smooth muscle "microsphincters" in the gastric mucosa of stingrays (Elasmobranchii, Dasyatidae)
Aaron C Henderson1, Stephan Bruns1, Shamsa Al Hameli1
1Biology Department, College of Science, UAE University, Al Ain, United Arab Emirates.
Abstract:
The occurrence of smooth muscle sphincters around gastric gland tubules in the cardiac stomach of some elasmobranch species is reported for the first time. These "microsphincters" took the form of a twisted torus, approximately 12-16 muscle fibres thick, that could fully constrict the gland tubules. However, their inconsistent positioning does not suggest a role in partitioning the tubules from the stomach lumen or in modulating secretory activity. Further research is required to ascertain the full taxonomic occurrence of these structures across the Elasmobranchii and to elucidate their function.
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