PUBLICATION

Muscarinic acetylcholine receptors in the brain of the zebrafish (Danio rerio) measured by radioligand binding techniques

Authors
Williams, F.E., and Messer, W.S. Jr.
ID
ZDB-PUB-040706-1
Date
2004
Source
Comparative biochemistry and physiology. Toxicology & pharmacology : CBP   137(4): 349-353 (Journal)
Registered Authors
Williams, Fred
Keywords
none
MeSH Terms
  • Animals
  • Brain/metabolism*
  • Kinetics
  • Muscarinic Agonists/metabolism
  • Muscarinic Agonists/pharmacology
  • Muscarinic Antagonists/metabolism
  • Muscarinic Antagonists/pharmacology
  • Radioligand Assay
  • Receptors, Muscarinic/metabolism*
  • Zebrafish/metabolism*
PubMed
15228953 Full text @ Comp. Biochem. Physiol. C Toxicol. Pharmacol.
Abstract
Muscarinic acetylcholine receptors (mAChRs) play a role in learning, memory and behavior in vertebrate animals. We measured the muscarinic cholinergic receptor levels in extracts from zebrafish (Danio rerio) brain by radioligand binding techniques. Saturation binding experiments with the radioligand [3H]-quinuclidinyl benzilate (QNB) were used to determine receptor number and relative affinity for several agonists and antagonists. Affinity at zebrafish brain receptors was relatively high with a K(d) of 40 +/- 5 pM. The number of receptors, represented by Bmax, was 63 +/- 16 fmol/mg protein. Oxotremorine and carbachol, agonists at muscarinic acetylcholine receptors, bound with displacement curves indicating multiple binding sites. In addition, oxotremorine bound with a higher affinity than did carbachol. The antagonist potency profile at zebrafish receptors in brain was determined to be atropine>>pirenzipine>p-fluoro-hexahydro-sila-difenidol>>otenzepad. The results obtained with zebrafish brain compare favorably to those found in insect, fish and mammalian species. Taken together, the binding results and favorable comparisons to mammalian systems indicate that zebrafish may provide a useful model organism for evaluating the role of cholinergic systems in learning, memory and behavior.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping