[Hormonal and vitamin regulation of glucose-6-phosphatases activity in the liver]

Glucose-6-phosphatase (G-6-Phase) activity in the rat liver is established to correlate directly with the content of corticosteroids in blood: it lowers with hypocorticoidism (adrenalectomy) and rises with hypercorticoidism (stress). The highest G-6-Phase activity in the liver of the intact animals is observed in autumn, the lowest one in spring, i.e. in the periods when the adrenals function has minimal and maximal values, respectively. Thiamin (0.4 g/kg) is shown to cause a decrease in the G-6-Phase activity in the liver of the intact rats and adrenalectomized or hypophysectomized animals. An assumption is advanced that the found in the experiment a pronounced insulin-like effect of vitamin B with respect to the G-6-Phase activity is connected with an intensified synthesis of the corresponding hormone in the pancreas.