Characterization of the delta-opioid receptor found in SH-SY5Y neuroblastoma cells.

Abstract

The delta-opioid receptor found in SH-SY5Y cells was characterized in terms of binding profile and ability to mediate the inhibition of forskolin-stimulated cAMP accumulation. Both DPDPE ([D-Pen2,D-Pen5]enkephalin) and deltorphin II, compounds reported to be selective for the delta 1- and delta 2-opioid receptor respectively, were potent agonists in these cells. Binding studies indicated that naltrindole benzofuran (NTB) had significantly higher affinity than 7-benzylidenenaltrexone (BNTX); however, both compounds have high affinity for the delta-opioid receptor found in SH-SY5Y cells. Naltrindole benzofuran was found to be a potent antagonist, with an IC50 of less than 1 nM, while 7-benzylidene naltrexone was found to be a relatively weak antagonist, requiring greater than 100 nM to inhibit 50% of agonist activity. Binding to intact SH-SY5Y cells was compared to binding to cell membranes and guinea-pig brain membranes. In each case, binding affinities were very similar. These studies suggest that the receptor found in SH-SY5Y cells could probably be classified as a delta 2-opioid receptor. However, the very similar binding characteristics of SH-SY5Y cells and guinea-pig brain membranes call into question the ability to label delta 1-opioid receptors.

• Authors: L Toll, W E Polgar, J S Auh
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 323 Issue 2-3 Pg. 261-7 (Apr 04 1997) ISSN: 0014-2999 [Print] Netherlands
• PMID: 9128848 (Publication Type: Comparative Study, Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Receptors, sigma
• Cyclic AMP

Topics

• Animals
• Binding, Competitive
• Brain (metabolism)
• Cyclic AMP (metabolism)
• Guinea Pigs
• Humans
• Membranes (metabolism)
• Neuroblastoma (metabolism, pathology)
• Receptors, sigma (drug effects, metabolism)
• Tumor Cells, Cultured (metabolism)