[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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In the previous study the author demonstrated that malnutrition during pregnancy inhibited the proliferation of the matrix cells, the precursors of neurons, in the embryonic mouse cerebrum, thus causing a decrease in the number of neurons in the cerebral cortex. In this experiment, the effects of maternal protein malnutrition on the matrix cells and the young neurons in the embryonic mouse cerebrum were studied ultrastructurally.
The pregnant mice of the ICR-JCL strain were divided into the control group and the experimental group. The sixteen-and 19day-old embryos, and the newborns from the mother animals fed on normal diet (25.5g of protein and 352 Cal. of energy per 100g) were served as the controls. The experimental group was subdivided into three groups. The sixteenday-old embryos and the newborns from the mother animals fed on low protein diet (0.7g of protein and 369 Cal. of energy per 100g) from the 8th to 16th day of pregnancy were designated as the group I and II respectively. The newborn mice from the mothers which were fed on the low protein diet from the 13th day of pregnancy to the term were designated as the group III.
When the mean body weight of the embryos in the group I was compared with that of age-matched controls, the former was about 20% less than the latter. The matrix layers and migratory zones in the brains of the normal 16day-old mouse embryos were composed of the matrix cells and immature neurons, which had oval nucleus and scanty cytoplasm. The scanty cytoplasm had a number of ribosomes.The nucleus had abundant chromatin. On the other hand, in the cerebral cortex of the malnourished embryos in group I, some degenerating cells were found in the matrix layer and migratory zone.Their cytoplasms were slightly swollen and showed a low electron density. The ribosomes in the cytoplasm were reduced in number. Occasionally, nuclear debris were also observed.
There was no difference in the mean body weight of the newborn mice between the group II and the controls. Electron microscopic study on the layers II and III of the cerebral cortices of the newborn mice in the group II showed no abnormalities.
In the group III, the pregnant mice were delivered of newborn mice one day prior to the term, i. e. on the 19th day of pregnancy. Thus, the newborn mice in this group were compared with the control fetuses of the 19th day of pregnancy.The mean body weight of the malnourished preterm newborn mice was about 49% less than that of the agematched controls. The width of cerebral cortex of malnourished preterm newborn mice was significantly smaller than that of the age-matched controls (P<0.001). Electron microscopic examination on the layers II and III in the cerebral cortex showed no degenerating changes in the group III.However, neuronal processes in the interspaces between cytoplasms of neurons decreased in number in the group III.

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The body movements are considered to be controlled by endogenous factor (central nervous system).The relationship between the body movements and the development of the central nervous system was polygraphically investigated.
All night polygraphic recordings were made in thirty-eight normal children (one month to fourteen years of age).Detection of the body move ments was achieved by the EEG artifact method.The body movements were analyzed by 1) BMs/min. (frequency of the body movements per minute), 2) % Epochs (percentage of the 20 second epochs with positive body movements in the total number of 20second epochs) and 3) % BMsT (the total duration of the body movements expressed as percentage to the total sleep time).
In total sleep, BMs/min., % Epochs and BMsT decreased rapidly until 3 months after birth, and did not change significantly from 4 months to 7 months of age.These decreased again until 10-12 months, and became constant after 12 months.In REM sleep, BMs/min., Epochs and % BMsT decreased rapidly until 3 months after birth, and thereafter tended to decrease with age.In NREM sleep, although BMs/min.and % Epochs were constant until 7months after birth, they decreased from 8 months to 10-12 months.Thereafter they became constant.% BMsT decreased until 10-12 months, and was constant thereafter.The changes in body movements during REM sleep were more remarkable than during NREM sleep.
These data suggest that the body movements during sleep reflect the development of the central nervous system, and may be useful for the diagnosis of central nervous disorders.

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