A New Method for Evaluation of Radioactive Label Transport Intensity in the Predominant Direction between Blood and Liver

Abstract

The intensity of 75 Se transport in the predominant direction after intraperitoneal injection of [ 75 Se]selenate was compared in 1-and 3-month-old rats receiving common vivarium ration or sucrose diet. The incorporation percent, blood/liver relative radioactivity, and relative radioactivity difference coefficient were evaluated in the blood and liver. The dynamics of label incorporation in the blood of rats fed common diets has two peaks (at 1-3 h and 12-24 h) and a drop at 6 h. Coefficient of difference in 1-month-old rats was characterized by a greater amplitude of fluctuations than in 3-month-old animals. . Address for corre spondence: kichenko@metronet.ru. S. M. Kichenko New methods for evaluation of compounds and atom transport can provide useful data for laboratory experiments and clinical diagnosis.The study of the transport of Se compounds is important [1,2,4,5,8]. The time of biological half-life of Se compounds in rat liver changes with age [6]; Se modifies the blood glucose level, gluconeogenesis intensity, and glycogenolysis in the liver of intact rats, in humans with diabetes and in rats with streptosotocin diabetes [7,[9][10][11][12]. However, there are no precise data on the intensity of Se transport between the blood and liver in the predominant direction during certain periods of time, which can be valuable for experimental and clinical medicine.The aim of this study was to develop a new method for evaluating the dynamics of 75 Se transport intensity in the predominant direction from the blood into the liver and vice versa. Age-specific differences in Se metabolism and relationship between carbohydrate and Se metabolism were studied. MATERIALS AND METHODSTotal 75 Se levels in liver homogenates and blood of rats 1, 3, 6, 12, 24, 48, and 192 h after intraperitoneal injection of [ 75 Se] sodium selenate (20,000 cpm/g) were evaluated by γ-irradiation of the sum of Se-containing compounds using a radiometer with a scintillation pickup with a Tl-activated KI crystal. The percent of 75 Se incorporation was estimated by the ratio of cpm/g tissue or 1 ml blood to cpm/g. The relative radioactivity (RRA) was estimated by the formula (1): % of incorporation in liver RRA=(1) % of incorporation in blood After a certain period after injection of the labeled compound, RRA was estimated by formula 1, and after fixed periods RRA 2 , RRA 3 , and RRA n were estimated.Then the predominant direction of 75 Se transport was determined and the difference between the trans-

Effect of parathyroidectomy on fluctuations in calcium transport between the blood and mineralized tissues of rats

“…Label fluctuations between the blood and mineralized tissues were studied by the previously described method [2] with minor modifications. Plasma Ca 2+ concentration was measured by the complexonometric method using ethylenediaminetetraacetic acid and murexide.…”