Assessment of a von Frey device for evaluation of the antinociceptive effects of morphine and its application in pharmacodynamic modeling of morphine in dogs.

摘要: OBJECTIVE: To assess the use of a von Frey device as mechanical nociceptive stimulus for evaluation antinociceptive effects morphine in dogs and its potential application pharmacodynamic modeling that species. ANIMALS: 6 healthy Beagles. PROCEDURE: thresholds were measured all before at intervals after they received no treatment (control dogs) i.v. administration sulfate (1 mg/kg; treated crossover study. The consisted rigid tip (0.5 mm diameter) an electronic load cell; operator was unaware recorded measurements. RESULTS: Application simple well tolerated by caused apparent tissue damage. No significant changes detected control 8 hourly measurements, indicating lack acquired tolerance, learned aversion, or local hyperalgesia. When assessed group, had significantly high 4 hours following administration, compared with baseline values; individually, decreased to values within (mean +/- SE) 2.8 0.6 hours. maximal effect (change from values) 213 43%, plasma concentration achieve 50% 13.92 2.39 ng/mL. CONCLUSIONS AND CLINICAL RELEVANCE: Data suggest that, dogs, dose mg/kg, i.v.) can be successfully achieved device.