Pharmacokinetics and Paw Withdrawal Pressure in Female Guinea Pigs (Cavia porcellus) Treated with Sustained-Release Buprenorphine and Buprenorphine Hydrochloride

• Published in: Journal of the American Association for Laboratory Animal Science Vol. 55; no. 6; pp. 789 - 793
• Main Authors: Smith, Brian J, Wegenast, Daniel J, Hansen, Ryan J, Hess, Ann M, Kendall, Lon V
• Format: Journal Article
• Language: English
• Published: United States American Association for Laboratory Animal Science 01-11-2016
• Subjects: Analgesics, Opioid - administration & dosage; Analgesics, Opioid - pharmacokinetics; Anesthesia; Animals; Animals, Laboratory; Buprenorphine - administration & dosage; Buprenorphine - pharmacokinetics; Delayed-Action Preparations - administration & dosage; Delayed-Action Preparations - pharmacokinetics; Female; Guinea Pigs; Humans; Pain - drug therapy; Pain - veterinary; Pain Management; Pain Measurement
• ISSN: 1559-6109

Providing appropriate analgesia is essential in minimizing pain and maintaining optimal animal care and welfare in laboratory animals. Guinea pigs are common animal models in biomedical research, often requiring analgesic support. Here we evaluated the pharmacokinetics and efficacy
of a sustained-release formulation of buprenorphine (Bup-SR) in this species. Guinea pigs (n = 7 each group) received either Bup-HCl (0.05 mg/kg BID for 3 d) or Bup-SR (0.3 mg/kg once). Plasma collection and measurement of paw-withdrawal pressure (PWP) was conducted at 0, 1, 3, 6,
12, 26, 48, and 72 h after treatment. Plasma levels of Bup-HCl peaked at 2331 pg/mL at 1 h after administration and declined to 165 pg/mL by 12 h. Plasma concentrations of Bup-SR peaked at 1344 pg/mL at 26 h after administration and declined to 429 pg/mL by 48 h. The PWP of the Bup-HCl-treated
guinea pigs peaked at 674 g at 1 h and declined to 402 g at 6 h, whereas that of Bup-SR-treated guinea pigs at 1 h was 361 g, 555 g at 6 h (significantly higher than that after Bup-HCl), and peaked at 680 g at 12 h. The PWP of both treatments was similar from 24 to 72 h and ranged from
348 to 450 g. The plasma concentration and PWP showed good correlation. These results suggest that Bup-SR provides consistent analgesia equivalent to that of Bup-HCl for a prolonged period of time and that Bup-SR is an alternative method of analgesia in guinea pigs.