Actions of two naturally occurring saturated N-acyldopamines on transient receptor potential vanilloid 1 (TRPV1) channels.
| Autor: | De Petrocellis, Luciano, Chu, Constance J., Moriello, Aniello Schiano, Kellner, Juliane C., Walker, J. Michael, Di Marzo, Vincezo, Di Marzo, Vincenzo |
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| Předmět: |
DOPAMINE
CATECHOLAMINES NEUROTRANSMITTERS BIOGENIC amines TISSUES CELLS FATTY acids CALCIUM metabolism AMIDES ANIMAL experimentation ARACHIDONIC acid BIOLOGICAL models CARRIER proteins CELL lines COMBINATION drug therapy COMPARATIVE studies DRUG receptors DRUG synergism DRUGS DRUG design DOSE-effect relationship in pharmacology CLINICAL drug trials HYPERALGESIA INFLAMMATION KIDNEYS LEG RESEARCH methodology MEDICAL cooperation POLYSACCHARIDES RATS RESEARCH EVALUATION research PAIN measurement DISEASE complications |
| Zdroj: | British Journal of Pharmacology; Sep2004, Vol. 143 Issue 2, p251-256, 6p |
| Abstrakt: | Four long-chain, linear fatty acid dopamides (N-acyldopamines) have been identified in nervous bovine and rat tissues. Two unsaturated members of this family of lipids, N-arachidonoyl-dopamine (NADA) and N-oleoyl-dopamine, were shown to potently activate the transient receptor potential channel type V1 (TRPV1), also known as the vanilloid receptor type 1 for capsaicin. However, the other two congeners, N-palmitoyl- and N-stearoyl-dopamine (PALDA and STEARDA), are inactive on TRPV1. We have investigated here the possibility that the two compounds act by enhancing the effect of NADA on TRPV1 ('entourage' effect). When pre-incubated for 5 min with cells, both compounds dose-dependently enhanced NADA's TRPV1-mediated effect on intracellular Ca(2+) in human embryonic kidney cells overexpressing the human TRPV1. In the presence of either PALDA or STEARDA (0.1-10 microm), the EC(50) of NADA was lowered from approximately 90 to approximately 30 nm. The effect on intracellular Ca(2+) by another endovanilloid, N-arachidonoyl-ethanolamine (anandamide, 50 nm), was also enhanced dose-dependently by both PALDA and STEARDA. PALDA and STEARDA also acted in synergy with low pH (6.0-6.7) to enhance intracellular Ca(2+) via TRPV1. When co-injected with NADA (0.5 micrograms) in rat hind paws, STEARDA (5 micrograms) potentiated NADA's TRPV1-mediated nociceptive effect by significantly shortening the withdrawal latencies from a radiant heat source. STEARDA (1 and 10 micrograms) also enhanced the nocifensive behavior induced by carrageenan in a typical test of inflammatory pain. These data indicate that, despite their inactivity per se on TRPV1, PALDA and STEARDA may play a role as 'entourage' compounds on chemicophysical agents that interact with these receptors, with possible implications in inflammatory and neuropathic pain. [ABSTRACT FROM AUTHOR] |
| Databáze: | Complementary Index |
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