Administering of I-125 preparation from blood of tortoise into organs of rats with experimental ovarian carcinoma

Full text: Complexes of substances of the peptide nature, received mainly from lymphoid bodies that normalize immune processes, are offered. The preparation 'Tortesin' can be related to this group. Tortesin is a drug isolated from the blood cells of the Central Asian tortoise, an animal with a unique radioresistance (LD50 = 100 Gy). During a short spring the tissues of tortoises produce biogenetic stimulators that can positively affect the organisms of irradiated animals. Tortesin acts by stimulating haemo- and immunopoietic systems and aids in recovery from radiation exposure. Thus, at animals treated with Tortesin, DNA and RNA synthesis in the bone marrow was enhanced, both antibody forming cells number and spleenic size increased, and haemopoietic parameters normalized. The survival rate also increased. That is why the determination of the point of initial application of the preparation is an important scientific objective. The research with the use of 125I was carried out for this purpose. The labeling was conducted via reaction with chloramine T. The preparation 125I issued by 'Radiopreparat' (Tashkent) was used. After the purification by chromatography the activity of 1000 impulse/min by 1 μg of protein was got. The experiment was carried out in the Center of oncology and radiology Republic of Uzbekistan. The including of the marker was being determined in young rats at the age of 1 month with an experimental ovarian carcinoma in 15 min, 1 hour and 1 day after the injection. The preparation was injected into the tail vein. The following 22 organs were examined: blood, ascitic fluid with cells, ascitic fluid without cells, tumor, liver, spleen, stomach, bowels, lungs, heart, testicles, kidneys, cerebral, marrow, thymus, fat, muscles, skin, thyroid gland, thigh-bone, tail, excrements. The results can be classified into three groups. The first group of organs (heart, cerebral, cells from tumor, thigh-bone, marrow, thyroid gland, thymus,) do not include the marker in any period of observation. The second group (liver, spleen, muscles, fat, testicles) includes a substantial amount of the marker. The maximum amount of including, 1000 impulse/min per 1g of tissue, was observed in 1 hour after the injection. Including of the marker is particularly significant in the third group. That is - blood, ascitic fluid without cells, stomach, bowels, lungs, skin, kidneys, excrements. The including of about 6000 impulse/min per 1g of tissue was observed there. It is interesting that all these organs are organs of excretion. We can assume that immediately after the injection all organs and systems start working for excretion of the marked preparation. Apparently, our preparation doesn't metabolize. This is illustrated by low level of the marker in liver and thyroid gland, which would otherwise contain 125-I. It is also illustrated by high level of the marker in excrements, which is 5 times higher than that in blood in 1-day period. As long as in all periods of observation the level of the marker in blood and ascetic fluid is lower than in stomach, bowels and lungs, it is obvious that in these tissues the marker was incorporated into cells. Although there is a barrier in some organs that doesn't let the marked preparation come in, in stomach and bowels some system collects and, possibly, keeps the preparation in cells. This can be connected with the function of excretion, which is inherent to these organs. It's interesting though, that number of stem cells particularly in these organs is relatively high. If we analyzed the results from this perspective we would get the following. The tissues that contain small amount of stem cells per unit of weight, almost doesn't include the marker. These are cells from heart, cerebral, tumor, thigh-bone and others. In the tissues of stomach, bowels and skin where a constant process of shelling of the surface cells takes place and where there are more stem cells, the volume of the marker is also large enough. The interaction between the preparation and cells of blood, thymus and bone m arrow is particularly interesting. We checked it with the marker on intact rats in vitro. However, the including was very little, 0,8%. This is the bottom margin of the mistake of the experiment. However, the calculations show that in this case 8 million molecules of the marker can be related to 1 cell. Possible change in the structure of the preparation after procedure of marking with chloramine T should be also taken into account. Further experiments in this direction can be connected with the usage of different types of the marker that don't modify native structure, like 14C or 3H, for example. (author)