Related Experiment Video
Updated: Jan 28, 2026
08:23
Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
4.8K
Evolution of nitric oxide regulation of gut function
Junko Yaguchi1, Shunsuke Yaguchi2
1Shimoda Marine Research Center, University of Tsukuba, 5-10-1 Shimoda, Shizuoka 415-0025, Japan.
Summary
Nitric oxide (NO) controls the relaxation of the pyloric sphincter in sea urchin larvae, similar to vertebrates. This finding suggests NO-dependent pylorus regulation is an ancient feature shared by deuterostomes.
Area of Science:
- Developmental Biology
- Neuroscience
- Comparative Physiology
Background:
- Gut passage in bilaterians is typically regulated by nerves and endodermally derived neuron-like cells.
- In vertebrates, enteric nerves release nitric oxide (NO) to control pyloric sphincter relaxation.
Purpose of the Study:
- To investigate the presence and function of nitric oxide synthase (nNOS)-positive cells in sea urchin larval sphincters.
- To determine if NO regulates pyloric sphincter relaxation in sea urchin larvae.
Main Methods:
- Immunohistochemistry using pan-neural marker Synaptotagmin-B (SynB).
- Detection of neuronal nitric oxide synthase (nNOS)-positive cells in sea urchin larval sphincters.
- Functional assays to assess NO's role in pyloric sphincter relaxation.
Main Results:
- Identified endoderm-derived nNOS-positive cells expressing SynB in sea urchin larval sphincters.
- Demonstrated that NO regulates the relaxation of the pyloric sphincter in these larvae.
Conclusions:
- NO-dependent pylorus regulation is a conserved feature within deuterostomes.
- This regulatory mechanism likely existed in stem deuterostomes.
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