MODEL FOR THE NEUROMUSCULAR COMPLICATIONS OF SYSTEMIC LUPUS-ERYTHEMATOSUS

The purpose of this study is to evaluate nerve and muscle physiology a nd histopathology in a murine lupus model. Muscle strength, compound m uscle action potentials (distal latency and amplitude), proximal limb muscle, sciatic nerve and joint specimens were studied in MRL/lpr (lup us model) and MRL/++ (control) mice. MRL/lpr mice showed decreased mus cle strength (P<10(-6), Wilcoxon rank sum), lower compound muscle acti on potential mean amplitude and prolonged distal latency (P = 0.005 an d 0.042, Mann-Whitney U-test), and muscle and nerve inflammation (P = 0.002 and P = 0.037, Fisher's exact test) compared with MRL/++ mice. T he MRL/lpr strain evaluated in this study demonstrated muscle weakness . abnormal motor nerve conduction studies and inflammation of both mus cle and nerve. These features make it an excellent model for studying the neuromuscular complications of lupus.