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View Full Version : Have Cannaboid receptors evolved in amphibians?


bullcowman
10-01-2004, 10:44 PM
I was wrong, I didn't think they did, but here:
Behavioral, pharmacological, and molecular characterization
of an amphibian cannabinoid receptor
by
Soderstrom K, Leid M, Moore FL, Murray TF
College of Pharmacy.
Department of Zoology,
Oregon State University,
Corvallis, Oregon, USA.
soderstrom@psy.fsu.edu
J Neurochem 2000 Jul; 75(1):413-23

ABSTRACT
Investigation of cannabinoid pharmacology in a vertebrate with a phylogenetic history distinct from that of mammals may allow better understanding of the physiological significance of cannabinoid neurochemistry. Taricha granulosa, the roughskin newt, was used here to characterize an amphibian cannabinoid receptor. Behavioral experiments demonstrated that the cannabinoid agonist levonantradol inhibits both newt spontaneous locomotor activity and courtship clasping behavior. Inhibition of clasping was dose-dependent and potent (IC(50) = 1.2 microgram per animal). Radioligand binding studies using [(3)H]CP-55940 allowed identification of a specific binding site (K(D) = 6.5 nM, B(max) = 1,853 fmol/mg of protein) in brain membranes. Rank order of affinity of several ligands was consistent with that reported for mammalian species (K(D), nM) : CP-55940 (3.8) > levonantradol (13.0) > WIN55212-2 (25.7) >> anandamide (1,665) approximately anandamide 100 microM phenylmethylsulfonyl fluoride (2,398). The cDNA encoding the newt CB1 cannabinoid receptor was cloned, and the corresponding mRNA of 5.9 kb was found to be highly expressed in brain. A nonclonal Chinese hamster ovary cell line stably expressing the newt CB1 cannabinoid receptor was prepared that allowed demonstration of cannabinoid-mediated inhibition of adenylate cyclase (EC 4.6.1.1) activity. This inhibition was dose-dependent and occurred at concentrations consistent with affinities determined through radioligand binding experiments. The behavioral, pharmacological, and molecular cloning results demonstrate that a CB1 cannabinoid receptor is expressed in the CNS of the roughskin newt. This amphibian CB1 is very similar in density, ligand binding affinity, ligand binding specificity, and amino acid sequence to mammalian CB1. The high degree of evolutionary conservation of cannabinoid signaling systems implies an important physiological role in vertebrate brain function.

Is it legal to do that at a univeristy??

groovygeckos
10-02-2004, 12:39 AM
whats wrong with admitting to using a medicinal herb ? dont think you would have to admit to that , for asking that question lol from my reading , pretty much every animal has developed receptors to my understanding ...... not sure why they would either .............. but hey there must be some actual purpose/reason/need for it on this earth , besides intoxication:)

bullcowman
10-02-2004, 02:16 AM
endo