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When administered via ip injection in rats, it was found that the test substance is incorporated intact into complex tissue components, such as phospholipids. It was also clearly shown that myo-inositol is vigorously metabolized to CO2 by the rat, 20-40% of the administered dose being excreted into the respiratory CO2 within 8 hours. Peak specific activity in the CO2 is reached in 1 to 2 hours.

Supplementation of the diet with myo-inositol in pregnant and lactating rats significantly increased the levels of myo-inositol in plasma, liver, kidney, and intestine of pups at all ages examined, and significantly increased the levels of myo-inositol in the milk and mammary tissue during lactation.

In nephrectomized rats, myo-inositol given via ip injection was accumulated rapidly within 1h by the thyroid, coagulating gland and seminal vesicle. Other tissues, such as the pituitary, prostate gland, liver and spleen, concentrated myo-inositol less actively. The muscle tissues studied (diaphragm and heart) concentrated little inositol, whereas brain, testis, and epididymal fat-pad did not concentrate it at all. The lipid fraction of liver contained most of the radio-labelled myo-inositol. In the other organs most of the radioactivity was found in the aqueous trichloroacetic acid extract, largely as free myo-inositol.

The absorption and distribution of myo-[inositol- 2-3H(N))hexakisphosphate was determined in rats. Of the total radioactivity, 79% was absorbed and at least 26% was degraded during the 24-hour period following ingestion. The absorption was rapid. Much of the radioactivity after 24 hours was in the liver, kidneys, muscle and skin. Analysis of plasma and urine demonstrated that most of the radioactivity was due to myo-inositol and small amounts of inositol monophosphate. Gastric epithelial cells, however, contained inositol and various inositol phosphates.

In man, approximately 8.6% of the total dose was excreted in the urine. It has been reported that the kidney is the major regulator of both the fasting plasma myo-inositol concentration and the myo-inositol pool size in man. The kidney is the major regulator of both the fasting plasma myo-inositol concentration and the myo-inositol pool size in man.