PANMYELOPHTHISIS WITH HEMORRHAGIC MANIFESTATIONS IN RATS ON A NUTRITIONAL BASIS

NUTRITIONAL CYTOPENIA (VITAMIN M DEFICIENCY) IN THE MONKEY

Young rhesus monkeys (Macaca mulatta) were given a diet containing casein, polished rice, whole wheat, salt mixture, sodium chloride, cod liver oil, and ascorbic acid. They developed a syndrome characterized by anemia, leukopenia, and loss of weight. Ulceration of the gums and diarrhea were common, and death occurred between the 26th and 100th day. 4 monkeys were given the deficient diet supplemented with 1 mg. of riboflavin daily, and these developed the characteristic signs and died. in periods of time similar to the survival of monkeys receiving the deficient diet alone. Nicotinic acid, either alone or in combination with riboflavin and thiamin chloride, failed to alter appreciably the course of the deficiency manifestations. Thus, it is evident that this nutritional cytopenia is not the result of a deficiency of vitamin B, riboflavin, or nicotinic acid. The deficient diet supplemented with either 10 gm. of dried brewers' yeast or 2 gm. of liver extract (Cohn fraction G) daily supported good growth, permitted normal body development, and maintained a normal blood picture over long periods. It is obvious that yeast and liver extract contain a substance essential to the nutrition of the monkey which is not identical with any of those factors of the vitamin B complex that have been chemically identified. We have proposed the term vitamin M for this factor which prevents nutritional cytopenia in the monkey.

CHOLINE AS A MEMBER OF THE VITAMIN B(2) COMPLEX

The experimental rations commonly used in studies on the vitamin B₂ complex are, as a rule, low in content of choline. Addition of vitamin B₆ has an aggravating influence on the specific effect of deficiency of choline, especially with regard to the development of cortical necrosis of the kidneys. The acute and subacute lesions associated with this specific type of renal injury are described. The renal lesions and fat infiltration of the liver, observed in rats kept on a vitamin B free diet, supplemented with thiamine, riboflavin and vitamin B₆, are indistinguishable from those attributed hitherto to cystine intoxication. Attention is drawn to the rôle of choline as a potential member of the vitamin B₂ complex and, in this connection, to the importance of the ratio cystine/methionine in the diet.

HEPATIC INJURY ON A NUTRITIONAL BASIS IN RATS

In forty-eight rats kept on a basal diet deficient in the vitamin B complex and supplemented with vitamin B(1) and riboflavin or with vitamin B(1), riboflavin and vitamin B(6), various pathological changes in the liver were observed. These changes were characterized mainly by parenchymatous and fatty degeneration, focal and massive necrosis, hyperemia and hernorrhage and, in some of the rats, by perilobular and condensation fibrosis. Addition of yeast or Peters' eluate (yeast extract) regularly prevented this hepatic injury. On the basis of the evidence obtained, it is assumed that the liver changes are of nutritional origin and should be correlated to deficiency of a part of the vitamin B(2) complex.

Selective adrenal necrosis and apoplexy induced by 7, 12-dimethylbenz(a)anthracene

Invariably in every normal rat a single dose of 7, 12-dimethylbenz(a)anthracene, by mouth or injected in a vein, was found to cause apoplexy and massive necrosis in the inner zones of the adrenal cortex; the zona glomerulosa, the adrenal medulla, and a small region of cortex adjacent to the great adrenal vessels were spared from damage. DMBA caused these selective lesions in females and in males of 2 strains of rats. Hemorrhage and necrosis were observed in no organ other than the adrenal gland. Whereas adrenal glands were heavily damaged by DMBA, pituitary and ovary escaped injury by the compound. A single huge but sublethal feeding of o, p'-DDD caused degenerative changes of minor magnitude in the adrenals and only in a small percentage of rats; the property of inducing adrenal damage was not shared by other polynuclear aromatic hydrocarbons which were investigated, including strong carcinogens. Presence of adrenal medulla is not a prerequisite to damage of the adrenal cortex by DMBA. The adrenal damage occurred in rats, given DMBA, from which the pituitary had been removed but the lesions were smaller in extent and less in incidence as post-hypophysectomy atrophy of the adrenal cortex progressed. The entire DMBA molecule was necessary to induce adrenal damage; fragments of this molecule did not induce adrenal lesions. Two components which are of cardinal importance in this specific damaging effect are: (a) electronic factor; (b) steric factor. The level of isocitric dehydrogenase in adrenal is modified considerably by presence or absence of estradiol-17beta.