buprenorphine and Rodent-Diseases

Extended-release (ER) local anesthetics can be used in multi-modal analgesia or in situations in which systemic analgesics may alter animal physiology and thus introduce interpretational confounds. In this study, we compared the analgesic efficacy of an ER buprenorphine formulation with that of a synergistic combination of ER bupivacaine and meloxicam. Female and male CD1 mice were randomly assigned to receive subcutaneous buprenorphine (3.25mg/kg) preemptively, subcutaneous infiltration of bupivacaine???meloxicam (0.03mL at incision closure (bupivacaine, 35mg/kg; meloxicam, 1mg/kg), or saline (10mL/kg SC) after induction of anesthesia. After laparotomy, mice were assessed for changes in daily body weight, rearing frequency, nest consolidation scores, time-to-integrate-nest test (TINT), and response to von Frey testing at 4, 8, 24, 48, and 72h after surgery. Daily weight, nest consolidation scores and rearing frequency were not significantly different among the 3 groups. TINT had fallen significantly response at 24 and 48h after injection in the ER buprenorphine group as compared with the saline and ER bupivacaine-meloxicam groups. Nociceptive thresholds, as assessed with von Frey testing, differed between saline controls and both analgesic groups at 4, 8, 24, 48, and 72 h after surgery. None of the mice in the bupivacaine???meloxicam group developed signs of neurotoxicity, a potential side effect of high-dose local anesthetics. This study demonstrates that local ER bupivacaine???meloxicam may be a useful alternative to systemic, ER buprenorphine for the relief of pain after laparotomy in mice.

Topics: Analgesics; Analgesics, Opioid; Anesthetics, Local; Animals; Bupivacaine; Buprenorphine; Female; Laparotomy; Male; Meloxicam; Mice; Pain; Pain, Postoperative; Rodent Diseases

This study was carried out to determine an effective regimen for pain management in streptococcal cell wall (SCW)-induced arthritis in female Lew/SSN rats. Forty weanling rats lin 2 groups) were trained to accept disks of jelly as part of their dietary regimen. At 8 weeks of age weighing 150 g, SCW arthritis was induced and sublingual buprenorphine tablets were incorporated into the jelly disks to alleviate the pain of acute arthritis, which developed 24 h post-induction. Group A rats received buprenorphine at a rate of 1 mg/kg 12 hourly. Group B rats received buprenorphine at a rate of 2 mg/kg 12 hourly. Both groups of rats were monitored for symptoms of distress using an adaptation of the Morton and Griffin scale of adverse reactions. Group A rats with severe arthritis required additional subcutaneous (s.c.) injections of buprenorphine to alleviate the adverse effects of arthritis. Group B rats, with twice the dose of buprenorphine did not require additional s.c. injections of buprenorphine. Histological sections of rat hocks indicated that the inflammation was suppressed in Group B rats. We concluded that oral administration of buprenorphine is an effective method of pain management in the pathogenesis of SCW-induced arthritis in Lew/SSN rats. In this model of arthritis, oral buprenorphine has a significant anti-inflammatory effect and appears to modulate the destructive arthritic phase in joints in this animal model of arthritis.

Topics: Administration, Sublingual; Animals; Anti-Inflammatory Agents; Appetite; Arthritis; Body Weight; Buprenorphine; Female; Palliative Care; Polysaccharides, Bacterial; Rats; Rats, Inbred Lew; Rodent Diseases

With ongoing animal welfare efforts, multimodal analgesia is often recommended to implement in study protocols. Buprenorphine with very potent analgesic effect is a standard opioid for the use in this context in rats. In this study, two rat strains (LEW/NHanZtm, n = 6 and Crl:CD(SD), n = 8) underwent orthopaedic surgery and received carprofen, buprenorphine and a local anaesthetic in a multimodal setup. Crl:CD(SD) rats showed severe side effects in the first 24 h after anaesthesia, predominantly manifesting in pica-behaviour and reaching humane endpoints in two of eight animals, while LEW/NHanZtm rats showed only slight depression in the first postoperative days. In the context of improving animal welfare in experimental studies, buprenorphine is highly recommended not to be used in male Crl:CD(SD) rats and should generally be used very carefully and only if required.

Topics: Analgesia; Analgesics; Analgesics, Opioid; Animals; Buprenorphine; Male; Pain Measurement; Pain, Postoperative; Rats; Rodent Diseases

Pain management in laboratory animals is generally accomplished by using opioids and NSAIDs. However, opioid use is hindered by controlled substance requirements and a relatively short duration of action. In this study, we compared the analgesic efficacy of firocoxib (a cyclooxygenase-2-selective NSAID) with that of buprenorphine in the mouse model of plantar incisional pain by objective measurement of mechanical allodynia and thermal hyperalgesia using von Frey and Hargreaves equipment, respectively. Our experimental design included 5 treatment groups: firocoxib at 10 mg/kg IP every 24 h (F10 group); firocoxib at 20 mg/kg IP every 24 h (F20); buprenorphine at 0.2 mg/kg SC every 8 h; intraperitoneal normal saline every 24 h; and sham group (anesthesia, no incision) treated with firocoxib at 20 mg/kg IP every 24 h (sham+F20). All mice underwent nociceptive assays at 24 h before and 4, 24, 48, and 72 h after surgery. Buprenorphine alleviated allodynia at all time points after incision. The F10 treatment alleviated allodynia at 4, 24, and 48 h, whereas F20 alleviated allodynia at 24, 48, and 72 h. None of the treatments alleviated thermal hyperalgesia at 4h. Except for F10 and buprenorphine at 24 h, all treatments alleviated thermal hyperalgesia at 24, 48, and 72 h. No significant differences were noted between the 2 doses of firocoxib and buprenorphine regarding mechanical allodynia and thermal hyperalgesia at all time points. In conclusion, the analgesic efficacy of firocoxib is comparable to that of buprenorphine in this mouse pain model.

Topics: 4-Butyrolactone; Analgesics, Opioid; Animals; Buprenorphine; Cyclooxygenase 2 Inhibitors; Female; Hyperalgesia; Mice; Mice, Inbred C57BL; Pain, Postoperative; Random Allocation; Rodent Diseases; Specific Pathogen-Free Organisms; Sulfones

A model system capable of providing clinically relevant analgesic doses with minimal trauma has been elusive in laboratory animal medicine. Our laboratory has developed an orofacial operant pain system that effectively discriminates between non-noxious and noxious thermal stimuli in rats and mice. Male and female rats (Crl:SD) and mice (Crl:SKR-HR(hr)) were trained to perform a task (placing their face through an opening and having their cheeks stay in contact with thermodes) to receive a reward (a solution of sweetened condensed milk). Currently accepted doses of buprenorphine were tested by using a crossover design. Pain was induced in both species by sensitizing the depilated skin over both cheeks with capsaicin cream or by creating a surgical incision (rats only) and then allowing the animals to contact a temperature-regulated thermode while obtaining a reward. Optimal antinociceptive doses included 0.05 and 0.1 mg/kg in male mice but only 0.05 mg/kg in female mice. In rats, optimal antinociceptive doses included 0.03 and 0.05 mg/kg for male rats but only 0.03 mg/kg for female rats. The 2 pain-induction models in rats (capsaicin cream and surgical incision) did not differ. Our orofacial operant pain assay can determine clinically relevant analgesic doses for rodents in a preclinical assay. The automated, investigator-independent nature of the assay, in conjunction with its high sensitivity, makes this method an improvement over traditional noninvasive methods, providing better data for developing optimal analgesic recommendations for rats and mice.

Topics: Analgesics; Analgesics, Opioid; Animals; Animals, Laboratory; Buprenorphine; Conditioning, Operant; Facial Pain; Female; Male; Mice; Pain Measurement; Rats; Rats, Sprague-Dawley; Reward; Rodent Diseases

Topics: Analgesics, Opioid; Animals; Buprenorphine; Dilatation, Pathologic; Gastric Dilatation; Injections, Subcutaneous; Male; Pica; Rats; Rats, Inbred F344; Rats, Wistar; Respiratory Distress Syndrome; Rodent Diseases

As a routine postoperative treatment, a single dose of buprenorphine was given to rats at a dose of 0.05 mg/kg subcutaneously. However, some rats developed abnormal secretions around the nose and mouth and some animals died 3-5 days after surgery and analgesic treatment. At autopsy a yellow fibrous mass was found in the stomach and intestines. Observations of animals given buprenorphine revealed an abnormal ingestion of bedding material. This caused a disturbance to normal digestion, with gastric distension, weight loss or decreased growth rate, constipation and occasionally death. In this study rats were monitored for 6 days following surgery and analgesic treatment. A comparison of growth rates was made between rats given saline and buprenorphine or nalbuphine and between animals kept on bedding or grid floors for the first 24h after treatment. Of the animals held on bedding, the buprenorphine-treated animals did not lose weight as the other animals did, but had on the other hand a decreased growth rate during the measuring period of 6 days after surgery. When denied access to bedding for the first 24 h after surgery, rats given saline or nalbuphine had a reduced weight gain over the first 24 h, similar to the groups held on bedding. Rats held on grid floors and given buprenorphine continued to gain weight for the first 24 h. From day 3, there was no significant difference between the groups, which all gained weight.

Topics: Analgesics, Opioid; Animals; Buprenorphine; Growth Disorders; Male; Rats; Rats, Sprague-Dawley; Rodent Diseases; Weight Gain