Spinal administration of selective opioid antagonists in amphibians: evidence for an opioid unireceptor
| Autor: | Leslie C. Newman, Craig W. Stevens |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Amphibian
Male medicine.medical_specialty Pyrrolidines Time Factors medicine.drug_class Narcotic Antagonists Pharmacology General Biochemistry Genetics and Molecular Biology Rana Functional evolution Opioid receptor biology.animal Internal medicine medicine Animals General Pharmacology Toxicology and Pharmaceutics Relative potency Receptor Injections Spinal Acetic Acid Benzofurans Pain Measurement Analgesics biology Chemistry Rana pipiens General Medicine Naltrexone Endocrinology Opioid Receptors Opioid Morphine Female Oligopeptides medicine.drug |
| Zdroj: | Life sciences. 64(10) |
| ISSN: | 0024-3205 |
| Popis: | In mammals, opioids act by interactions with three distinct types of receptors: mu, delta, or kappa opioid receptors. Using a novel assay of antinociception in the Northern grass frog, Rana pipiens, previous work demonstrated that selective mu, delta, or kappa opioids produced a potent antinociception when administered by the spinal route. The relative potency of this effect was highly correlated to that found in mammals. Present studies employing selective opioid antagonists, beta-FNA, NTI, or nor-BNI demonstrated that, in general, these antagonists were not selective in the amphibian model. These data have implications for the functional evolution of opioid receptors in vertebrates and suggest that the tested mu, delta, and kappa opioids mediate antinociception via a single type of opioid receptor in amphibians, termed the unireceptor. |
| Databáze: | OpenAIRE |
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