Immunohistochemical localization of RANK, RANKL and OPG in healthy and arthritic canine elbow joints.

Objective: To determine if the receptor activator of nuclear factor-kappaB-receptor activator of nuclear factor-kappaB ligand-osteoprotegerin (RANK-RANKL-OPG) system is active in bone remodeling in dogs and, if so, whether differences in expression of these mediators occur in healthy and arthritic joints.

Study Design: Experimental study.

Sample Population: Fragmented processus coronoidei (n=20) were surgically removed from dogs with elbow arthritis and 5 corresponding healthy samples from dogs euthanatized for reasons other than elbow joint disease.

Endothelin antagonism prevents diabetic retinopathy in NOD mice: a potential role of the angiogenic factor adrenomedullin.

Altered activity of retinal endothelin-1 (ET-1) and nitric oxide may play a causal role in the hemodynamic and histopathological changes of diabetic retinopathy. This study evaluated the therapeutic potential of long-term selective blockade of the ET-1(A) receptor (ETRA) to prevent the development of retinopathy in a genetic mouse model of nonobese type 1 diabetes (NOD). Mice with NOD that received subcutaneous implantation of insulin pellets and wild-type control mice were treated for 4 months with the selective ETRA antagonist LU208075 (30 mg/kg/day) via drinking water.