The use of cyclosporine-A in dogs with chronic osteoarthritis: a pilot study.

OBJECTIVE: To evaluate the efficacy of cyclosporine-A in dogs with radiographic and physical evidence of chronic stifle osteoarthritis. MATERIALS AND METHODS: Ten hound-type dogs with osteoarthritis induced by surgical transection of a cranial cruciate ligament followed by immediate stabilization of the stifle four years prior to study start were randomized to two groups. Cyclosporine-A was administered orally once daily at 5 mg/kg to one group for one month while the other group served as control. After a two week wash-out period during which the animals were not treated, and the degree of lameness was allowed to return to baseline, the treatments were switched so that the second group received treatment with cyclosporine-A and the first group served as control. Ground reaction forces were measured using a force platform in all animals at day zero and then every two weeks until the end of the study. RESULTS: Cyclosporine-A did not alter the degree of lameness based on assessment of ground reaction forces. CONCLUSIONS: At a dose of 5 mg/kg/day for 28 days, cyclosporine-A was not effective in decreasing lameness of dogs with chronic osteoarthritis induced by surgical transection of the cranial cruciate ligament.

Immunohistochemical detection of retinoid receptors in tumors from 30 dogs diagnosed with cutaneous lymphoma.

BACKGROUND: Retinoids exert their effects by binding to retinoid receptors. Two types of retinoid receptors have been described: retinoic acid receptor (RAR) and retinoid X receptor (RXR), and their subtypes α, ß, and γ. The expression of subtypes varies depending on the disease process. This study intended to detect the pattern of retinoid receptor expression in cutaneous lymphomas in dogs. HYPOTHESIS: Cutaneous lymphomas in dogs have variable expression of retinoid and retinoid X receptors. ANIMALS: Biopsy specimens from 30 dogs with cutaneous lymphoma. METHODS: Tissues of dogs with cutaneous lymphoma were evaluated by immunohistochemistry for expression of retinoid receptors. The tissues were tested for the presence of 3 RAR and RXR subtypes (α, ß, and γ). Lymphoma immunophenotype was determined by the use of the immunohistochemical markers CD79a (B-cell) and CD3 (T-cell) in all cases. RESULTS: Twenty-nine of 30 dogs were CD3 positive. The retinoid receptors expressed with the greatest frequency were RARß (87% of cases), and RXRα and RXRγ (77% of cases). The expression of RARγ was not observed. CONCLUSIONS AND CLINICAL RELEVANCE: Retinoid and rexinoid receptor binding drugs may have an impact on the treatment of dogs with cutaneous lymphoma.