Back to Search
Start Over
beta3 subunit is present in different nicotinic receptor subtypes in chick retina
- Source :
- European journal of pharmacology. 393(1-3)
- Publication Year :
- 2000
-
Abstract
- Although the neuronal nicotinic beta3 subunit was cloned several years ago, it has only recently been shown to form heteromeric channels when associated with other nicotinic subunits, and very little information is available concerning its assembly in the native nicotinic receptors of the nervous system. Using subunit-specific antibodies and immunoprecipitation experiments, we have identified the retina as being the chick central nervous system (CNS) area that expresses the highest level of the beta3 subunit. Sequential immunopurification experiments showed that there are at least two populations of beta3-containing receptors in chick retina: in one, the beta3 subunit is associated with the alpha6 and beta4 subunits; in the other more heterogeneous population, the beta3 subunit is associated with the alpha2, alpha3, alpha4, beta2 and beta4 subunits. Both of these receptor populations bind [3H]epibatidine and a number of nicotinic receptor agonists with high affinity (nM) and nicotinic receptor antagonists with a lower affinity (microM). The greatest pharmacological difference between the two populations is the affinity for the alpha-conotoxin MII, which inhibits binding to alpha6-containing receptors and not that to beta3-containing receptors. We also searched for the presence of the beta3 subunit associated with the alpha-bungarotoxin binding subunits alpha7 and/or alpha8 in retina and chick brain. Immunoprecipitation studies using anti-beta3 antibodies did not detect any specific alpha-bungarotoxin labeled receptors, thus, indicating that the beta3 subunit is not present in the alpha-bungarotoxin receptors of these areas.
- Subjects :
- medicine.medical_specialty
animal structures
alpha7 Nicotinic Acetylcholine Receptor
Pyridines
Protein subunit
Biology
Receptors, Nicotinic
Tritium
Gamma-aminobutyric acid receptor subunit alpha-1
Retina
Interleukin 10 receptor, alpha subunit
Ganglion type nicotinic receptor
Internal medicine
medicine
Animals
Protein Isoforms
Nicotinic Agonists
Receptor
Pharmacology
Dose-Response Relationship, Drug
Bridged Bicyclo Compounds, Heterocyclic
Cell biology
Endocrinology
Nicotinic agonist
Carbachol
Alpha-4 beta-2 nicotinic receptor
Chickens
Cys-loop receptors
Subjects
Details
- ISSN :
- 00142999
- Volume :
- 393
- Issue :
- 1-3
- Database :
- OpenAIRE
- Journal :
- European journal of pharmacology
- Accession number :
- edsair.doi.dedup.....95a49d15479312db7b6435d480ff6ae5