Vitamin D2 promotes the absorption of calcium by the brush border of the small intestinal mucosa and the reabsorption of phosphorus by the renal tubules, increases the concentration of blood calcium and phosphorus, and cooperates with parathyroid hormone (PTH) and calcitonin (CT) to promote the release of calcium phosphate from old bones, maintain and regulate normal plasma calcium and phosphorus concentrations. Vitamin D2 promotes the deposition of calcium in new bone formation sites, deposits citrate in bones, promotes bone calcification and the maturation of osteoblast function and bone-like tissue. After vitamin D2 is ingested, it is catalyzed by the 25-hydroxylase system in the cell microsomes to produce calcidiol (25-OHD3), which is catalyzed by the 1-hydroxylase system of the renal proximal tubular cells to produce biologically active calcitriol [1-25-(OH)2D3].

Vitamin D2 promotes the absorption of calcium by the brush border of the small intestinal mucosa and the reabsorption of phosphorus by the renal tubules, increases the concentration of blood calcium and phosphorus, cooperates with parathyroid hormone (PTH) and calcitonin (CT), promotes the release of calcium phosphate from old bones, and maintains and regulates the normal concentration of plasma calcium and phosphorus. Vitamin D2 promotes the deposition of calcium in new bone formation sites, deposits citrate in bones, promotes bone calcification and osteoblast function and bone-like tissue maturation. After vitamin D2 is ingested, it is catalyzed by the 25-hydroxylase system in the cell microsomes to produce calcidiol (25-OHD3), which is catalyzed by the 1-hydroxylase system of the renal proximal tubular cells to produce biologically active calcitriol [1-25-(OH)2D3]. In animal experiments, after the parathyroid glands of mice were removed, the activity of 1-hydroxylase was lost and calcitriol could not be synthesized. In hypercalcemia, CT secretion increases and 1-hydroxylase activity is inhibited, which reduces the conversion of calcidiol to calcitriol. This confirms that calcitriol metabolism is regulated by PTH and CT, and that phosphate and calcium can also regulate the activity of 1-hydroxylase.

It is oxidized in the body to phenobarbital and phenethyl malonamide, which have anti-epileptic activity. Its anti-epileptic effect is similar to that of phenobarbital, but its intensity and toxicity are lower. It is rapidly and completely absorbed orally, reaching the peak plasma concentration in about 3 hours. The half-life is about 8 hours, and the plasma protein binding rate is 20%. It can easily pass through the blood-brain barrier, the placenta, and appear in breast milk. At therapeutic concentrations, it can reduce the excitatory effect of glutamate, enhance the inhibitory effect of gamma-aminobutyric acid, inhibit monosynaptic and polysynaptic transmission of the central nervous system, lead to a decrease in the excitability of the entire nerve cell, and increase the electrical stimulation threshold of the motor cortex. It can increase the threshold of seizures and inhibit the spread of discharges of epileptic foci.

It is oxidized in the body to phenobarbital and phenethyl malonamide, which have anti-epileptic activity. Its anti-epileptic effect is similar to that of phenobarbital, but its intensity and toxicity are lower. It is rapidly and completely absorbed orally, reaching the peak plasma concentration in about 3 hours. The half-life is about 8 hours, and the plasma protein binding rate is 20%. It can easily pass through the blood-brain barrier, the placenta, and appear in breast milk. At therapeutic concentrations, it can reduce the excitatory effect of glutamate, enhance the inhibitory effect of gamma-aminobutyric acid, inhibit monosynaptic and polysynaptic transmission of the central nervous system, lead to a decrease in the excitability of the entire nerve cell, and increase the electrical stimulation threshold of the motor cortex. It can increase the threshold of seizures and inhibit the spread of discharges of epileptic foci.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.

The nine vitamins contained in this product are important components of various coenzymes and hormones in the human body. They are essential substances for maintaining normal metabolism and good health. Their deficiency can cause metabolic disorders and lead to various diseases.