Abstract
The influence of nicotine upon the chick embryos, especially the growth of bone (long bone) was investigated histopathologically.
Applying 1.0 mg, 5.0 mg and 7.0 mg of nicotine per one egg, the eggs were opened on the 10 th, 15 th and 20 th day of incubation.
In measuring thier humerus and femur, inhibition of growth was recognized in comparison with the control, especially remarkable in high concentration of nicotine.
The same could be said with the body weight of the chick embryo.
A decrease of osteoblasts, undergrowth of cart silage periosteum, degeneration of cartilage bone-cells and nuclei, alternation of slightness of bonebeam and incomplete absorption of cartilage and others were recognized.
These findings ware especially remarkable in the egg applied with a high concentration of nicotine.
However, the systematic alternation in the eggs opend on the 20 th day was milder than those opened on the 15 th day, and it was more significant in cartilage than in bone. (So that the influence of nicotine was more remarkable on cartilage)
In the present experiment, the imperfect development of the bones by nicotine should be classiified as a hyperlastic type of Chondrodystrophia foetalis.
