Sasco sprague dawley rats

Postnatal day 3 (P3) SASCO Sprague-Dawley rats purchased from Charles River Laboratories were used for preparing cochlear organotypic cultures as described previously (Ding et al., 2011 (link)). In brief, after rat pups were decapitated, the cochleae were quickly removed and the whole basilar membrane containing the organ of Corti, auditory nerve fibers (ANF) and SGN were carefully dissected out and transferred on to rat tail collagen gel in a culture dish. Approximately 10 μl of collagen gel (type I collagen gel 3.76 mg/ml in 0.02 N acetic acid, 10x basal medium eagle, 2% sodium carbonate, at 9:1: 1 ratio) was applied to the surface of a 35 × 10 mm culture dish and allowed to gel for about 30 min at room temperature. Afterwards, 1.3 ml of serum-free medium (0.01 g/ml bovine serum albumin (Sigma A-4919), 1% serum-free supplement (Sigma I-1884), 1% 200 mM glutamate, 2.4% of 20% glucose, 0.2% penicillin G, 95.4% 1X basal medium eagle (Sigma B-15220) was added to the culture dish. The basilar membrane containing the sensory hair cells, SGN and supporting cells was placed on the surface of the collagen gel and then maintained in an incubator at 37 °C and 5% CO₂ overnight. On the following day, fresh culture medium (2 ml) with or without various concentrations of TMT was added to each dish and cochlear explants were cultured for an additional 24 h.

We used adult (age 3-5 months) male, albino SASCO Sprague-Dawley rats from Charles River Laboratories (Wilmington, MA). We followed the National Institute of Health Guide for the Care and Use of Laboratory Animals (NIH Publications No. 80-23) revised 1996. Animal experiments were reviewed and approved by the Institutional Animal Care and Use Committee of the University at Buffalo. All animals had ad lib. access to water and standard laboratory rodent chow. They were housed individually and maintained on a 12 hour light-dark cycle.

An established rat femoral segmental defect model was utilized to preliminarily assess the osseointegration potential of PEEK-SP compared to smooth PEEK surfaces [26 (link)]. This model was chosen based on its previous use in characterizing bone ingrowth in porous polymeric and metallic implants [27 (link)–30 (link)]. All surgical procedures were approved by the Institutional Animal Care and Use Committee at the Georgia Institute of Technology (IACUC protocol #A11028). Briefly, bilateral 8 mm femoral defects were made in the central diaphyses of three 13-week old female Sasco Sprague-Dawley rats (Charles River), totaling six defects. Femurs were stabilized prior to defect creation using a modular plating system consisting of a polysulfone plate and two stainless steel risers. PEEK implants with one surface porous and one smooth end face were press-fit into each defect before incision closure (n=6). The orientations of surface porous faces were alternated between contralateral limbs. After surgery animals were allowed to recover and ambulate freely. Animals were injected with slow release buprenorphine at the time of surgery to relieve any pain. One animal was euthanized at 6 weeks and the remaining two were euthanized at 12 weeks.

Thirty-six male SASCO Sprague-Dawley rats (3 to 4 months old, mean body weight of 325 ± 50 g, Charles River Laboratories, Wilmington, MA) were used in this study. Twelve rats were used in Experiment I, Experiment II and Experiment III. All procedures in this study were reviewed and approved by the University at Buffalo Institutional Animal Care and Use Committee in accordance with NIH guidelines for the use and care of animals in research.

Fifty adult male SASCO Sprague-Dawley rats (200–250g; Charles River Laboratories, Wilmington, Mass., USA) were used for the conditioned place preference study and were group housed (2–3 rats/cage) in individually ventilated Innovive rat cages (San Diego, CA, USA). Eight adult male Sprague Dawley rats (200–250g; Charles River Laboratories) were used for drug self-administration procedures and were individually housed in standard Plexiglas containers. All animals received food and water available ad libitum and were maintained in a temperature and humidity controlled colony on a 12-h light/dark cycle (lights on at 0700 and off at 1900). All studies were conducted in accordance with the Guide for the Care and Use of Laboratory Animals as adopted by the National Institutes of Health and procedures were approved by the University of New England Institutional Animal Care and Use Committee (IACUC). The health of the animals was assessed daily by laboratory technicians and animal care staff.

For these studies, 13-week-old female SASCO Sprague Dawley rats (Charles River Laboratories, Inc.) were used. Rats were pair housed in individually ventilated caging (Tecniplast) with a tunnel and gnawing blocks (Bio-Serv) for enrichment. Bedding was a mixture of corn cob and processed paper. Purina Mills International #5001 was fed ad libitum. Filtered tap water treated with ultraviolet light was provided ad libitum in bottles. Sentinel results from Charles River Laboratories International Rat Prevalent PRIA testing were negative for all pathogens in the housing room. All animals were allowed to acclimate for at least 2 weeks before any procedures were performed. Following each procedure, a divider was temporarily placed in the cage for better monitoring of post-operative recovery. Animals were randomly allocated to treatment groups. All procedures in this study were approved by the Georgia Institute of Technology Institutional Animal Care and Use Committee in compliance with Federal regulations governing the protection of animals in research.

Unilateral critically sized segmental bone defects were created in the left femora of 13-week-old female SASCO Sprague-Dawley rats (Charles River Laboratories, Wilmington, MA) as detailed previously [39 (link)]. Briefly, a radiolucent polysulfone plate was first attached to the femur to stabilize it, and an 8mm mid-diaphyseal bone segment was excised. Defects were treated with 30 μg BMP-2 in collagen sponge or in alginate hydrogel, both surrounded by a PCL nanofiber mesh as described above (n=9–11). Slow release buprenorphine (Wildlife Pharmaceuticals, Windsor, CO) was given subcutaneously for analgesia. At the conclusion of the experiments, animals were euthanized by CO₂ inhalation. All procedures were approved by the Georgia Institute of Technology Institutional Animal Care and Use Committee (IACUC).