|
KMID : 0378019720150100087
|
|
New Medical Journal
1972 Volume.15 No. 10 p.87 ~ p.93
|
|
|
Experimental Study of Uptake of Zn in Fractured Bones
|
|
|
|
|
Abstract
|
|
|
Fifty four mice were divided into 2 groups; 27 as the normal control and the rest as the fractured group, after breaking their femur manipulatively.
Each group was subdivided into subgroups according to the date of sacrifice after a single injection of (65)^ZnCI_(2); 3 hours, 1 day, 3 days, 1 week, 2 weeks, and 3 weeks. In every run of experiment, soft tissue such as liver, kidney, skeletal muscle, skin, fractured bone, and control femur were sampled and their radioactivities were counted. The distribution kinetics of the injected 65Zn were analyzed. The results obtained were as follows.
1. SA-time curve of (65)^Zn in soft tissue such as kidney, liver, skeletal muscle and skin reached its peak at 3 hour and declined steeply until 3 days; thereafter the curve decreased exponentially showing straight line in semilogarithmic paper. In bone, on the other hand, the curve showed a steady increase until one week when it showed a peak and then decreased exponentially as in soft tissues.
Such a kinetic characteristics may indicate that Zn in various tissue equilibriates with that of body pool and a regular turnover takes place.
2. With the slope of SA-time curve in various tissues of each group the turnover rate of absorbed 65Zn and the halftime (t1), time required for an half of tissue Zn to be turned over, is calculated using first order kinetic equation. The turnover rate was 58 in liver, 68 in kidney, 27 in skeletal muscle, 40%/wk in bones of the control group; the halftime was 1.19, 1.02, 2.56 and 1.73 wk respectively. It could be seen that the turnover rate of Zn increased in proportion to the metabolic rate of the soft tissues.
In fractured group, on the other hand, turnover rate of (65)^Zn in soft tissue increased in all tissues except kidney, and that especially highly in skeletal muscle. But on the contrary turnover rate in fractured bone decreased markedly compared to normal bones.
3. Maximum value of the SA of (65)^Zn in various tissue was compared; they were high in liver,kidney, skeletal muscle and skin, in that order. There was a distinct difference-in Zn concentration of various tissue. Exceptionally high value was observed in bone than in other soft tissues; SA of 65Zn of fractured bone, showed a statistically significant difference and persistently high value throughout the course of the experiment.
From above data it was reasonable to suppose that the turnover takes place vigorously in various tissues and freeing of Zn is accelerated in order to supply the increased Zn requirement in fractured bone.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|