The Effects of Growth Hormone on Pubertal Maturation

Chung, So Chung; Kim, Duk Hi

Abstract

PURPOSE
The recombinant human growth hormone is widely used to improve short stature but it was reported that GH therapy might accelerate sexual maturation especially short girl. We tried to find out the effects of GH on pubertal progression in female rat.
METHODS
In animal experiment, forty female Sprague-Dawley rats were treated with rhGH(1U/kg). GH was given subcutaneously daily for 5weeks since 25day of life. We measured body weight and length twice a week, vaginal opening and epithelial change were observed daily. We checked the serum estrogen and insulin-like growth factor- I concentration weekly. The results were compared to 40 control female rats.
RESULTS
1) Body weight increased significantly in GH treated group(P<0.05). 2) Serum IGF- I concentration increased significantly after GH treatment(P<0.05). 3) Vaginal opening occurred on postnatal 34.3+/-1.9day in GH treated group and 35.4+/-2.2day in control group(p>0.1). First diestrous phase of puberty was noted on postnatal 36.8+/-1.9day and 38.3+/-3.0day, respectively(p>0.1). 4) The difference of serum E2 concentration of two group was insignificant.
CONCLUSIONS
GH administration in female rats increased body weight and length without accelerating of pubertal maturation compared to control group. So GH treatment will give a good favor on final height.