Abstract
To investigate the relationship between motor end plate size and muscle fiber diameter, analyses of 125I-.alpha.-bungarotoxin autoradiographs and acetylcholinesterase staining were performed in different muscle groups of the rat. These revealed (1) there is a linear correlation between end plate size and fiber diameter in each muscle group, and (2) each muscle group has a characteristic ratio of endplate size to fiber diameter; the ratios were markedly higher in extraocular muscles than in limb muscles.