Modulation of submucosal cholinergic neurons by 5-hydroxytryptamine and neuropeptides
| Autor: | William M. Yau, M. L. Youther, J. A. Dorsett |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
medicine.medical_specialty
Serotonin Physiology Enkephalin Methionine Vasoactive intestinal peptide Neuropeptide Myenteric Plexus Galanin Biology In Vitro Techniques Substance P Dynorphins chemistry.chemical_compound Ileum Physiology (medical) Internal medicine medicine Submucous plexus Animals Cholinergic neuron Myenteric plexus Neurons Hepatology Neuropeptides Gastroenterology Dynorphin A Muscle Smooth Acetylcholine Electric Stimulation Endocrinology Jejunum chemistry Female Rabbits Peptides Somatostatin medicine.drug Vasoactive Intestinal Peptide |
| Zdroj: | The American journal of physiology. 259(6 Pt 1) |
| ISSN: | 0002-9513 |
| Popis: | Release of [3H]acetylcholine ([3H]ACh) was examined in a submucous plexus preparation obtained from the guinea pig small intestine in vitro. Constant-current field stimulation evoked ACh output; this output was dependent on the stimulus frequency applied. Maximal release was observed at 10 Hz; this release was blocked by tetrodotoxin (1 x 10(-6) M) or in Ca2(+)-free buffer. Serotonin [5-hydroxytryptamine (5-HT)] stimulated the release of ACh dose dependently, with an ED50 of 5 x 10(-7) M. Substance P was ineffective, while vasoactive intestinal peptide weakly stimulated ACh secretion. Several neuropeptides were tested on their ability to modulate 5-HT-evoked ACh release. Dynorphin A inhibited 5-HT-stimulated ACh release, while Met-enkephalin was without any effect. Both somatostatin and galanin were effective modulators, with an inhibitory effect in the submicromolar range and an excitatory effect at higher concentrations. The response characteristics of the cholinergic neurons of submucosal plexus differ markedly from those of the myenteric plexus. These distinct features form an important framework for future functional studies on submucous plexus neurons. |
| Databáze: | OpenAIRE |
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