Quantitative Changes of Holmes Positive Nucleolus-like Inclusion Bodies in the Mouse Locus Coeruleus under Various Experimental Conditions

The author demonstrated earlier that the nucleolus-like inclusion bodies in the central nervous system observed under an electron microscope are characteristically stained by the modified Holmes silver impregnation method. These inclusion bodies were then counted in the entire mouse brain; they numbered 1,547±144 on the unilateral side of the locus coeruleus. In the present experiment, mice were subjected to various experimental conditions or given several medicaments that might induce changes in body weight and in the number of inclusion bodies. Following dehydration, fasting, dehydration with fasting, induction of stress condition, reserpine, α-methyl-p-tyrosine, cycloheximide, cephalexin and puromycin administrations, body weight was decreased along with a decrease in the number of inclusion bodies in the locus coeruleus. After streptomycin sulfate injection, however, body weight was increased and inclusion bodies showed a moderate increase in number. Actinomycin D and mitomycin C, inhibitors of nucleic acid synthesis, brought about a definite decrease in body weight, but little if any changes in the number of inclusion bodies. Furthermore, after reserpine injection several small inclusion bodies were observed in the cytoplasm of locus coeruleus cells in a recovery stage and after inclusion bodies regained their normal number and size. The results suggested that the inclusion bodies might have some relation to body weight, as well as to monoamine of the brain and protein synthesis.