[Dynamics of vitamin A metabolism in the blood and semen of karakul ram sires]. / Dinamika obmena vitamina A v krovi i semeni baranov-proizvoditelei karakul'skoi porody.

Dynamics of vitamin A turnover in the blood and semen of astrakhan ram-sires was being studied for determining the ways of its transport to mature sperms. By means of high pressure liquid chromatography it was found that concentrations of retinol in the blood and retinyl palmitate in the semen of rams, suffering from hypovitaminosis A, rose simultaneously during the first 24 hours after feeding the animals with labelled retinol. According to the data on the specific activity of labelled vitamin A in the blood and semen a significant portion of the vitamin was transfered into the semen from the blood together with the secretions of epididymis and/or another sexual glands. The role of vitamin A in epididymal sperm maturation is discussed. A more prolonged increase of vitamin A levels in the blood and semen of the animals under study was achieved after double feeding of each animal with 60 mg of vitamin A.

[Determination of retinol in human blood plasma using high pressure liquid chromatography]. / Opredelenie retinola v plazme krovi cheloveka metodom zhidkostnoi khromatografii vysokogo davleniia.

A quantitative procedure for estimation of retinol in human blood plasma using high pressure liquid chromatography involved separation of the retinoids on an reversed phase analytical column. C19-retinoid aldehyde was used as an internal standard. The procedure enabled to detect up to 0.015 microgram of retinol/ml of blood plasma and may be used for routine clinical analyses.