骨折 및 性홀몬이 骨組織內 Ca45 沈着에 미치는 影響 = Effect of Fracture and Sex Hormones on Ca^(45) Deposition in Mouse Bone.

다국어 초록 (Multilingual Abstract)

Effect of fracture and sex hormones on Ca45 deposition in bone was studied with the homogenate of the fractured and non-fractured femora of mice.

Two hundred and forty male mice weighing 25gm. approximately were divided into two major groups; one and the other in vitro.

Each group was subdivided into four groups; control, estrogen, androgen and progesterone. Normal saline was used as control. In the in vivo experiment, 2.5 mg. of sex hormones, estrogen, androgen and progesterone, were injected subcutaneously at an interval of 24 hours for 3 days.
The Ieft femur was fractured manually on the day of last administration of the hormone. On the 2nd, 4th and 6th days after fracture, each group of mice were sacrificed and both femora were recovered.
Each femur was immersed for 24 hours in 30c.c. of the Krebs Ringer phosphate containing 0. 2pc of W502 In the in vitro experiment, the left femur was fractured without administering sex hormones.

Both femora were recovered as in vivo and were immersed in the Ca45 Krebs Ringer phosphate containing same amount of sex hormones of as in the in vivo experiment, on the 2nd, 4th and 5th days after fracture and were left for 48 hours.
Each femora was then incubated, dried, pulverized and dissolved with strong hydrochloric acid, and
neutralized with IN NaOH. Adding ammonium oxalate, the solution developed precipitation.
The Ca content(mg/gm bone, radioactivity(epm) and specific activity of the precipitate were determined. The following conclusions were obtained from the experiment:
1. There was no remarkable change in the amount of Ca in bone, in either the fractured or non-

fractured bone, in vivo or in vitro and whether sex hormones were admip_istered or not.

2. The fractured bone showed slightly increased specifc activity of Ca compared with the non-fractured

bone, the rate of increase of specific activity being androgen, estrogen and progesterone, in that order.

3. The acceleration rate of specific activity of Ca in vitro closely resembles the in vivo experiment,

suggesting that sex hormones are capable of acting directly on bone.