Dataset Information

Serotonin receptor diversity in the human colon: Expression of serotonin type 3 receptor subunits 5-HT3C, 5-HT3D, and 5-HT3E.

ABSTRACT: Since the first description of 5-HT? receptors more than 50 years ago, there has been speculation about the molecular basis of their receptor heterogeneity. We have cloned the genes encoding novel 5-HT3 subunits 5-HT3C, 5-HT3D, and 5-HT3E and have shown that these subunits are able to form functional heteromeric receptors when coexpressed with the 5-HT3A subunit. However, whether these subunits are actually expressed in human tissue remained to be confirmed. In the current study, we performed immunocytochemistry to locate the 5-HT3A as well as the 5-HT3C, 5-HT3D, and 5-HT3E subunits within the human colon. Western blot analysis was used to confirm subunit expression, and RT-PCR was employed to detect transcripts encoding 5-HT? receptor subunits in microdissected tissue samples. This investigation revealed, for the first time, that 5-HT3C, 5-HT3D, and 5-HT3E subunits are coexpressed with 5-HT3A in cell bodies of myenteric neurons. Furthermore, 5-HT3A and 5-HT3D were found to be expressed in submucosal plexus of the human large intestine. These data provide a strong basis for future studies of the roles that specific 5-HT? receptor subtypes play in the function of the enteric and central nervous systems and the contribution that specific 5-HT? receptors make to the pathophysiology of gastrointestinal disorders such as irritable bowel syndrome and dyspepsia.

SUBMITTER: Kapeller J

PROVIDER: S-EPMC3056486 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Serotonin receptor diversity in the human colon: Expression of serotonin type 3 receptor subunits 5-HT3C, 5-HT3D, and 5-HT3E.

Kapeller Johannes J Möller Dorothee D Lasitschka Felix F Autschbach Frank F Hovius Ruud R Rappold Gudrun G Brüss Michael M Gershon Michael D MD Niesler Beate B

The Journal of comparative neurology 20110201 3

Since the first description of 5-HT₃ receptors more than 50 years ago, there has been speculation about the molecular basis of their receptor heterogeneity. We have cloned the genes encoding novel 5-HT3 subunits 5-HT3C, 5-HT3D, and 5-HT3E and have shown that these subunits are able to form functional heteromeric receptors when coexpressed with the 5-HT3A subunit. However, whether these subunits are actually expressed in human tissue remained to be confirmed. In the current study, we performed im ...[more]

PMID: 21192076

Similar Datasets

Project description:Irritable bowel syndrome (IBS) is a chronic disease that causes abdominal pain and an imbalance of defecation patterns due to gastrointestinal dysfunction. The cause of IBS remains unclear, but intestinal-brain axis problems and neurotransmitters have been suggested as factors. In this study, chanoclavine, which has a ring structure similar to 5-hydroxytryptamine (5-HT), showed an interaction with the 5-HT3A receptor to regulate IBS. Although its derivatives are known to be involved in neurotransmitter receptors, the molecular physiological mechanism of the interaction between chanoclavine and the 5-HT3A receptor is unknown. Electrophysiological experiments were conducted using a two-electrode voltage-clamp analysis to observe the inhibitory effects of chanoclavine on Xenopus oocytes in which the h5-HT3A receptor was expressed. The co-application of chanoclavine and 5-HT resulted in concentration-dependent, reversible, voltage-independent, and competitive inhibition. The 5-HT3A response induced by 5-HT was blocked by chanoclavine with half-maximal inhibitory response concentration (IC50) values of 107.2 µM. Docking studies suggested that chanoclavine was positioned close F130 and N138 in the 5-HT3A receptor-binding site. The double mutation of F130A and N138A significantly attenuated the interaction of chanoclavine compared to a single mutation or the wild type. These data suggest that F130 and N138 are important sites for ligand binding and activity. Chanoclavine and ergonovine have different effects. Asparagine, the 130th amino acid sequence of the 5-HT3A receptor, and phenylalanine, the 138th, are important in the role of binding chanoclavine, but ergonovine has no interaction with any amino acid sequence of the 5-HT3A receptor. The results of the electrophysiological studies and of in silico simulation showed that chanoclavine has the potential to inhibit the hypergastric stimulation of the gut by inhibiting the stimulation of signal transduction through 5-HT3A receptor stimulation. These findings suggest chanoclavine as a potential antiemetic agent for excessive gut stimulation and offer insight into the mechanisms of 5-HT3A receptor inhibition.

Dataset Information

Serotonin receptor diversity in the human colon: Expression of serotonin type 3 receptor subunits 5-HT3C, 5-HT3D, and 5-HT3E.

Publications

Serotonin receptor diversity in the human colon: Expression of serotonin type 3 receptor subunits 5-HT3C, 5-HT3D, and 5-HT3E.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets