The Use Of Nucleic Acid Metabolism Of Rats After Oral Administration Kinetics And Nucleic Acid Research

A research on histological absorption and distribution of the nucleic acid (Ribonuclic acid RNA) produced by Dalian Zhen-Ao Nucleic Acid Science & Technology Development Co., Ltd. was performed under commission of the company. Upon agreement by both parties, the sensitive and distinctive radioactive tracing technique was used to determine the RNA concentration in blood, absorbing situation of the RNA in rats in different orally intaking time and dosages, and the absorption rate of RNA by rats under 80mg/kg intaking dosage was studied also. Under 80mg/kg orally intaking dosage, the distribution of the metabolite contents of RNA in rats'main visceral organs (brain, thyroid gland, thymus gland, heart, lung, liver, spleen , stomach, small intestine, colon, kidney, testicle, womb, muscle and skin) was detected in 0.5 , 1.0 , 4.0 and 10.0 hrs after the rats orally taking RNA product. A small amount of H in the molecular structure of RNA product being studied was replaced by radioactive ~3H, then mixed appropriate amount of ~3H-RNA with the RNA reagent to prepare the experimental reagent, after the experimental animal took the reagent, radioactive intension of tissues and blood of them were detected, from which the contents of metabolism outcome of RNA in the tested sample were calculated. The experiment was carried out in the national recognized radioactivity laboratory and national second grade animal room which meeting its qualifications. The experiment data was counted by the EXCEL and several medicine dynamical parameters were calculated by medicine dynamical software package(DAS).The result demonstrates:1. The high radioactive activity and radioactive purity of the ~3H-RNA reagent satisfies the request of the research.2. The distinctiveness, sensitivity and stability of the radioactive tracing technique is applicable to this research.3. A high absorption rate(85.50%) was obtained after the rats orally taking RNA reagent under 80mg/kg dosage. This result is illustrated by the percentage of the ratio of area under the curve of the concentration in blood-time(AUC) of the ~3H-RNA reagent(80mg/kg) taken orally between injected through rats'tail vein.4. Fairly good curve of the concentration in blood-time was observed under 40 mg/kg, 80mg/kg and 160 mg/kg orally intaking dosages, the higher the dosage is and the bigger the area(AUC) under curve of the concentration in blood-time curve is. But there is no direct proportion relationship between them.5.4 hrs after the rats taking the RNA, the metabolites'concentration in blood all reaches their summits under 40 mg/kg,80mg/kg and 160 mg/kg orally intaking dosages.6. The RNA metabolites are distributed in every organ of the rat in 0.5 , 1.0 , 4.0 and 10.0 hrs after the rat taking 80mg/kg dosage orally. It is noticeable that the RNA metabolites contents are higher in nerve, endocrine and the immune systems in addition to stomach and intestine.7. A certain amount of RNA metabolite is still maintained in tissues at 10.0 hrs after the rat taking 80mg/kg dosage orally. This is an indication of that the RNA has been used by the tissues.The above results indicates that the RNA product orally taken by the rat is enzymatic hydrolysised into small molecular, then absorbed by intestinal epithelial cell. The absorption rate reachs 85.50% under 80mg/kg orally intaking dosage. The RNA metabolite are equally distributed in tissues. A certain amount of RNA metabolite is still maintained in tissues in 10.0 hrs after the rat taking orally, which indicates that RNA may be used by the tissues. All this results are very useful to application of RNA products in the field of health care foods and drugs. The utility of external source nucleic acid was studied by scholars in the middle of 50's, and it was proved that orally taken RNA products can be enzymatic hydrolysised into small molecular in alimentary canal, part of them can be used by in tissues during nucleated cell multiplication, but the way by which they are used was not reported. Here RNA labeling radioactive tracing technique is used to study the using circumstances of the oral taken ~3H -RNA by the rat, by detecting radioactive intension of the cell multiplication organs, such as blood, thymus gland, liver, spleen , testicle etc. in 4, 12 and 24 hrs after the rat taking ~3H -RNA orally. Result illustrates: Radioactivity is detected in the nucleic acid in blood,thymus gland, liver, spleen and testicle of the rat after taking ~3H -RNA orally, showing that RNA is used in different degree, a little amount is used in 4 hrs, and the using ratio increasing in longer intaking time. Among them, bone marrow and blood cell make use of RNA more , liver and spleen are in the middle, thymus gland and testiculus are a little few.