TOTAL NUMBER AND SIZE DISTRIBUTION OF MOTOR-NEURONS IN THE SPINAL-CORD OF NORMAL AND EMC-VIRUS INFECTED MICE - A STEREOLOGICAL STUDY

The encephalomyocarditis virus of the diabetogenic M-strain (EMC-M) is known to cause diabetes in mice. The EMC-M virus has also been shown to cause paresis in some of the infected animals. The clinical feature s include an acute ascending predominantly motor paralysis, developing within days. This resembles acute idiopathic polyneuritis. The alpha motor neurons would be a possible target for the virus, so two paramet ers, the total number and the size distribution of motor neurons, were therefore selected for further investigation in 6 mice with neurologi cal involvement and compared with 6 control mice. The optical fraction ator method was applied for estimating the total number of motor neuro ns and the 3D size distribution was estimated using the rotator method in a vertical design. No difference was found in the total number of motor neurons and the size distributions were similar in the 2 groups, This design can be used as a model for the estimation of the tc,tal n umber of motor neurons and their size distribution in other experiment al animal models.