Abstract
Investigations were undertaken histologically on the eosinophilic and basophilic cells of the anterior pituitary and neurosecretory substance of the hypothalamus and posterior pituitary in riboflavin deficient rats. Observations were also made on the distribution of riboflavin in the diencephalon and pituitary of normal and riboflavin loaded rats. It was found that eosinophilic and basophilic cells of the anterior pituitary increase in the early stage of riboflavin deficiency but decrease later, and this change was more marked in the eosinophils. Neurosecretory cells in the supraoptic nucleus and paraventricular nucleus, and neurosecretory substance in the posterior pituitary decrease when riboflavin deficient symptoms become marked. Recovery took place when 50μg of riboflavin daily was given for 2-3 weeks. Distribution of riboflavin in the diencephalon and pituitary was high in the neurosecretory cells of the supraoptic nucleus and eosinophilic cells of the anterior pituitary. From the above observation, it was confirmed that the diencephalon-pituitary function was stimulated in the early stage of riboflavin deficiency, and it was more marked in the areas where the distribution of riboflavin was high.
