Alpha2 adrenergic receptors are located prejunctionally in the Auerbach's plexus of the guinea pig small intestine: Direct demonstration by radioligand binding
| Autor: | Robert J. Lefkowitz, Jarl E.S. Wikberg |
|---|---|
| Rok vydání: | 1982 |
| Předmět: |
Male
Agonist medicine.medical_specialty Adrenergic receptor medicine.drug_class Guinea Pigs Myenteric Plexus Biology Tritium Clonidine General Biochemistry Genetics and Molecular Biology Guinea pig Radioligand Assay Internal medicine Intestine Small Prazosin medicine Animals General Pharmacology Toxicology and Pharmaceutics Binding site Receptor General Medicine Receptors Adrenergic alpha Ligand (biochemistry) Small intestine Receptors Adrenergic Endocrinology medicine.anatomical_structure medicine.drug |
| Zdroj: | Life Sciences. 31:2899-2905 |
| ISSN: | 0024-3205 |
| Popis: | We provide direct evidence that alpha 2 -receptors in the guinea pig small intestine are localized prejunctionally in neurons of the Auerbach's plexus. The alpha 2 -agonist ligand [ 3 H]clonidine bound to a single saturable class of sites with a K d of 1–2 nM and a capacity of approximately 70 fmol/mg protein in membranes from the innervated longitudinal and circular muscle layers of the intestine. By a special dissection technique the Auerbach's plexus could be completely removed from the longitudinal muscle. In these denervated preparations the clonidine binding sites were virtually completely removed whereas the expected binding was observed in innervated controls. The innervated preparations also contained a small number of alpha 1 -receptors as revealed by binding with [ 3 H]prazosin (capacity approximately 18 fmol/mg protein with a K d of 0.4-0 3 7 nM). Thus, the present study suggests that alpha 2 -receptors ([ 3 H]clonidine binding sites) are localized in neurons (i.e., prejunctionally) in the Auerbach's plexus of the guinea pig small intestine. |
| Databáze: | OpenAIRE |
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