Sixty of ovariectomized albino rats were divided into 3 groups; first group for control, second group for estrogen stimulated group and third group for progesterone stimulated group.
In each group, uterine . tissues were excised by sacrificing at 1 or 2 week after ovariectomy, and homogenated by glass, homogenizer with-C14-glucose incubation medium in which were added universally labeled C14-glucose and non radioactive glucose into Krebs-Ringer phosphate buffer so as to maintain the. glucose concentration of 200 mg % .
About 5 ?g of estradiol was injected subeutaneously in the second group and 10 mg of progesterone in the third group at 10 hours before sacrificing the ovariectomized rats of respective group.
Tissue homogenate obtained from each group was incubated for a period of 4 hours by Dubnoff metabolic shaking incubator.
At the end of experiment, concentrations of glucose and glycogen and radioactivities of glycogens were analyzed from homogenate samples and total CO_2 production rates and radioactivities of CO_2 from the CO_2 samples which were trapped in the center well of reaction flask in the each run of each group.
From the data obtained in each group, the effect of stimulation of ovarian hormone on the oxidative metabolism of C^14-glucose and turnover rate of glycogen of uterine tissues were observed as follow.
1) Glucose consumption rates were mean of 3.10?M/hr/gm in the first group, 3.34 ?M/hr/gm in the second group and 4.78,?M/hr/gm in the third group.
There were little difference in glucose consumption rates between control and estrogen stimulated groups, but glucose consumption rate in progesterone stimulated group increased about 54% of control value.
2) Total CO2 production rates were mean-of 3.5,?M/hr/gm, in the control group, 14.5 ?M/hr/gm in the second group and 16.2 ?M/hr/gm in the third group.
There are remarkable increase in oxidative metabolism of uterus by stimulation of ovarian hormone.
Relative specific activities (RSA), which were the fractions of CO2 derived from C14-glucose to total
CO2 production rates, were calculated average of 7.0% in the first group. 27.0% in the second group - and 20.5% in the third group.
C02 production rate from medium C´4-glucose showed average of 0.25 ?M/hr/gm which is equivalent only 1.3% (RGDco2) of glucose consumption rate in the control. Therefore, contribution of glucose on the oxidative metabolism is negligible in the control tissue. However, C02 production rates from glucose in the ovarian hormone stimulated groups. were remarkably increased showing average of 0.65 ?M/hr/gm which value is about 16 times of control value in the second group and 6.55 ?M/hr/gm which is about 13.8 times of control in the third group.
RGDco2, which are fractions of glucose consumed into respiratory C02 to total glucose consumption rates, were ean of 19.5% in the second group and 11.6% in the third group.
From the above data, it seems that ovarian hormone stimulate the oxidation of glucose in the uterine tissue.
3) Concentrations of glycogen were mean of 0.49 mg/gm in the first group, 1.44 mg/gm in the second group and 0.85 mg/gm in the third group. There is prominent increase in the estrogen stimulated group.
In each group, concentration of glycogen were maintained relatively constant value during experimental period and difference of SA of medium C´4-glucose and -SA of glycogen were decreased exponentially with time, showing straight line on the semilogarhythrnic paper. Therefore, turnover of glycogen in the uterine tissue is followed by first order kinetic reaction.
Turnover rates calculated by first order kinetic equation showed 1.72 % /hr in the control, 12.65 % /hr in the second group and 9.77%/hr in the third group.
Glycogen turnover increased prominently by ovarian hormone.
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