Investigation of the antinociceptive activity of buprenorphine in sheep

Abstract

Buprenorphine given intravenously (6 μg kg−1) was examined for its antinociceptive activity in unrestrained sheep using devices to measure thermal and mechanical thresholds The plasma levels of buprenorphine following intravenous injection over the time period of the antinociceptive testing were measured using a radioimmunoassay. Buprenorphine produced a clear antinociceptive effect lasting for up to three and a half hours when measured by the thermal threshold test, but no detectable antinociception in the mechanical test. The plasma levels of buprenorphine indicated that the drug was rapidly distributed in a manner not dissimilar to that reported in man, although individual animals showed a wide variation in some parameters. When plasma levels of the drug were high (< 700 pg ml−1) during the first sixty minutes, no antinociceptive activity in the thermal test could be detected, which may be due to the slow receptor kinetics shown by this drug.

PK‐PD modeling of buprenorphine in cats: intravenous and oral transmucosal administration1

“…dosing were recorded within the first 5 min. These data are similar to those reported in sheep where plasma concentrations up to 700 pg/mL (0.7 ng/mL) were reported during the first hour but analgesia was not evident until after 60 min (Nolan et al. , 1987).…”

“…, 2003a). The slow onset but long duration of this opioid is thought to be related to slow receptor binding and disassociation (Nolan et al. , 1987).…”

Pharmacokinetics of intravenous and intramuscular buprenorphine in the horse

“…In humans and sheep, antinociceptive effects of buprenorphine are found at very low plasma concentrations, 1 and 0.7 ng/mL, respectively (Watson et al. , 1982; Nolan et al. , 1987).…”

Abstracts presented at the 10th World Congress of Veterinary Anaesthesia, 31st August–4th September 2009, Glasgow, UK

“…The pharmacokinetic profile of buprenorphine administered IV and IM to alpacas shows a mean terminal half-life longer than that observed in small ruminants (Ingvast-Larsson et al 2007, Nolan et al 1987, but shorter than that observed in cats. Average time to Cmax after IM buprenorphine is more rapid in alpacas when compared to oral administration in cats (Robertson et al 2005).…”