維生素B12-Co60 在大白鼠體內之分布及生物半衰期 作者:繆端生、陳之安

摘要：

1. 本實驗利用Co60之γ射線作追蹤劑，將濃度0.012μe（或0.01077μe）之維生素B12－Co60 0.5c.c.，以肌肉注射方法， 注射於大白鼠之後肢大腿肌肉內，以作維生素B12－Co60 在腎臟、肝臟、心臟、胰臟、腸、胃、等 組之分布情形之研究，並求維生素B12－Co60 在該等組織內半衰期，以及鼠每日排出物中維生 素B12－Co60 之含量。
2. 維生素B12－Co60在組織中分布情形，就整個組織吸收百分率而言，注射最先五天內以腸胃最高， 達18.36％，胰臟最低微1.31％；五天之後腎臟13.51％居最高位，而胰臟為1.03％仍為最低。 就計數/克重量而言，腎臟高達2460計數克，一直居最高位，而腸為645計數/克，為最低者。 以計數/克重量為計數單位，較有意義，蓋可影射組織代謝之旺盛程度。
3. 排出物之含量，注射後第一天之排出量高達注射總量之7.18％，到十天左右後，每日排出量趨於穩定在1.38％到0.84％之間。
4. 生物半衰期，Co60 之生物半衰期在不同組織各不相同，最長為心臟，計49.5天，次之為胃計49天；最短為腸計9.5天。

《詳全文》

The Distribution and Biological half Life of Vitamin B12-Co60 in Albino Rat Author: Tuan-Sheng Miu, Ruth Chen

Abstract：

1. Using Co60 as the tracer, each Albino rat of Sprague-Dawley Strain was administrated 0.5c.c. this radioactive vitamin B12 intramuscularly. The biological half-life ane the distribution of vitamin Bl2-Co60 in kidney, liver, heart spleen, intestine and stomach of rat are determined.
2. Expressing in count by % of total tissue, intestine was found to be the tissue which took up the largest part of the traacer dose in the first five days after injection. However kidney became the top most tissue in distri-bution, while that of the others were in the sequence: liver, stomach, intestine, heart and spleen,
3. Expressing in count by counts/gm., the kidney took up the largest part of vitamin B12-Co60, The uptake in the other tissue decreased in the sequence: stomaoh, spleen, intestine, liver and heart.
4. The biological half-life of Co60 or vitamin B12 in heart is 49.5 days which is the longest among all the tissues studied, stomach stands the next 48 day ; while intestine is the shortest 9.5 days.
5. Little more than 7% of the total dose injected was excreted in the excreta within 24 hours. The amount of excretion decreased gradually each day followed and reached to 1.38% to 0.84% per day, ten days after injection.