The aim of this study was to evaluate the pharmacokinetics and the pharmacodynamics of this drug in red-eared slider turtles, after a single intramuscular injection of 5 mg/kg of TAP. Turtles (n = 9) were randomly assigned to two treatment groups, according to an open, single-dose, single-treatment, unpaired, two-period crossover design. Group A (n = 5) received a single IM dose of TAP (5 mg/mL) at 5 mg/kg. Group B (n = 4) received a single IM injection of saline (equivalent volume to opioid volumes) of TAP. After a 1-month wash out period, groups were rotated and the experiment repeated. TAP plasma concentrations were evaluated by a validated HPLC-FL method, while an infrared thermal stimuli was applied to the plantar surface of the turtles’ hind limbs to evaluate the thermal withdrawal latency (TWL). TAP plasma concentrations were detectable between 1-24 h (2141 – 42 ng/mL, respectively). The TAP treated group showed a dramatic increase in TWL 1 hour after drug administration (15.31 4.73 s). Subsequently, TWL decreased with time, significant differences between treatment and control groups were apparent up to 10 h following treatment. A linear relationship (r2 = 0.98) between TAP plasma concentration and effect was found. Given these qualities, TAP appears to be an attractive option for antinociception in turtles, due to its rapid onset and acceptable duration of effect.
|Autori:||Giorgi, Mario; De Vito, V.; Owen, H.; Demontis, M. P.; Varoni, M. V.|
|Titolo:||PK/PD evaluations of the novel atypical opioid tapentadol in red-eared slider turtles|
|Anno del prodotto:||2014|
|Appare nelle tipologie:||1.1 Articolo in rivista|