INNER-EAR DEFECT SIMILAR TO ALPORTS-SYNDROME IN THE GLOMERULOSCLEROSIS MOUSE MODEL MPV17

The Mpv17 mouse strain is a recessive transgenic mouse mutant that dev elops glomerulosclerosis and nephrotic syndrome at a young age. The ph enotype results from a loss of function of a gene coding for a hydroph obic peroxisomal protein of 176 amino acids of 20 kDa following its de struction by retroviral integration. To investigate a potential effect of the missing Mpv17 function on the inner ear light and electron mic roscopic investigations were performed on the inner ears of Mpv17 mice and controls. These revealed degeneration of the stria vascularis and spiral ligament, loss of cochlear neurons and degeneration of the org an of Corti. The alterations observed here were similar to those descr ibed for Alport's syndrome, an inherited disorder characterized by pro gressive nephritis and neurosensory deafness. These findings indicate that although the molecular cause is different, the Mpv17 mouse model may share pathological mechanisms involved in patients with Alport's s yndrome. At present the Mpv17 mouse appears to be a suitable animal mo del for this disease and may help to further elucidate the relationshi p between the kidney and the inner ear.