These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Expression of ganglia-type nicotinic acetylcholine receptors and nicotinic ligand binding sites by cells of the IMR-32 human neuroblastoma clonal line.
    Author: Lukas RJ.
    Journal: J Pharmacol Exp Ther; 1993 Apr; 265(1):294-302. PubMed ID: 8474012.
    Abstract:
    Studies were conducted to ascertain whether cells of the IMR-32 human neuroblastoma clone express ligand binding sites and functional responsiveness attributable to ganglia-type nicotinic acetylcholine receptors (nAChR) and/or neuronal/nicotinic alpha-bungarotoxin binding sites. Some comparative studies were conducted using cells of other clonal lines, including BC3H-1 mouse muscle line cells that are known to express muscle-type nAChR. Two classes of specific binding sites for 3H-labeled acetylcholine ([3H]ACh) and a single class of high-affinity, specific 125I-labeled alpha-bungarotoxin binding sites are expressed on membrane fractions prepared from IMR-32 cells. Radioligand binding to these sites on IMR-32 cells is relatively insensitive to blockade by the muscle-type nAChR-selective inhibitors, succinyldicholine and decamethonium, indicating that they are distinct from muscle-type nAChR. [3H]ACh binding to its sites on IMR-32 cell membranes is insensitive to blockade by alpha-bungarotoxin, indicating that IMR-32 cell [3H]ACh and 125I-labeled alpha-bungarotoxin binding sites also can be distinguished. Functional nAChR ion channels of the ganglia-type are expressed by IMR-32 cells, as assessed by the abilities of nicotinic agonists to stimulate 86Rb+ efflux, the relatively higher sensitivity of those responses to blockade by mecamylamine than by d-tubocurarine, and the inability of alpha-bungarotoxin to antagonize nAChR function. These results are consistent with expression by IMR-32 cells of functional ganglia-type nAChR that correlate with high affinity [3H]ACh binding sites as well as expression of a distinct class of neuronal/nicotinic alpha-bungarotoxin binding sites that have a ganglia-type pharmacology.
    [Abstract] [Full Text] [Related] [New Search]