Postmenopause-Like Bone Loss by Mammary Carcinoma Walker256/S Which Secretes Luteinizing Hormone-Releasing Hormone

The Japanese Journal of Pharmacology

Yukie Saitoh¹  Ken-ichi Miyamoto¹  Yoshihiro Waki¹  Shinya Yamamoto¹  Shohei Kasugai²  Keiichi Ohya² 

[1] Department of Pharmacology and Pharmaceutics, Graduate School of Natural Science and Technology, Kanazawa University;Department of Pharmacology, Faculty of Dentistry, Tokyo Medical and Dental University

关键词: Walker 256/S carcinosarcoma;    Osteoporosis;    Estrus cycle;    Menopause;    Luteinizing hormone-releasing hormone (LH-RH);   

DOI  :  10.1254/jjp.80.119

学科分类：药理学

来源: Nihon Yakuri Gakkai Henshuubu / Japanese Pharmacological Society

【 摘 要 】

References(23)Cited-By(1)When Walker 256/S carcinosarcoma (W256/S) was subcutaneously inoculated into the back of mature female Wistar Imamichi rats (10-week-old), the tumor grew rapidly and caused increases in the urinary excretions of calcium and hydroxyproline, without changes in the serum concentrations of calcium and inorganic phosphorus. Furthermore, osteoporosis-like changes in the femurs and decrease in uterus weight were observed, as previously reported for W256/S-bearing young rats. In the healthy mature female rats, the estrus cycle passed through four stages (proestrus, estrus, metestrus and diestrus) within 4 to 5 days, with a peak of serum estradiol and progesterone levels in the proestrus stage. On the other hand, after subcutaneous inoculation of W256/S into the rats, the estrus cycle tended to pause upon the metestrus or diestrus stage, accompanied with significantly low estradiol and progesterone levels in serum. W256/S tumor produced and secreted luteinizing hormone-releasing hormone (LH-RH). In conclusion, it seems that the ectopical secretion of LH-RH from the tumor resulted in the decrease in the secretion of gonadotropic hormones, following low level of sex hormones and stopping the estrus cycle. Therefore, W256/S-bearing rats may be a model for osteoporosis of hypoovarianism or postmenopause.

【 授权许可】

Unknown