Endocrine Abstracts

We have previously reported that treatment in vivo with estrogenic compounds or vitamin D metabolites increased the specific activity of creatine kinase specific activity (CK) in different organs both in intact and in ovariectomized female rats. In the present study we assessed the hormonal responsiveness of para-uterine fat from female and epididymal fat from male rats. Injection of immature female rats with 5 μg estradiol-17β (E2), 50 μg of e...

3,5,3′-triiodothyronine (T3), regulates energy metabolism by oxygen consumption and thermogenesis via induction of NaK-ATPase in vivo. These changes are correlated with nuclear T3 binding in responsive organs. We showed that creatine kinase (CK) another ATP regulating enzyme, is modulated by different hormones, in tissues containing appropriate receptors. This modulation is via binding to specific receptors and changes in CK mRNA levels. Since CK is involved in en...

We have previously demonstrated that rat bone cells in vivo and in vitro, responded sex-specifically to gonadal steroids in stimulation of the specific activity of creatine kinase (CK). Pretreatment with vitamin D analogs upregulated the sex-specific responsiveness and sensitivity to gonadal steroids. We also found that mice cultured femoral bone marrow (BM) in the presence of dexamethasone (DEX), 1.25(OH)2D3 (1.25D) or both, differentiated into osteoblast-like c...

Vitamin D metabolites modulate creatine kinase specific activity (CK) in cultured skeletal cells. In this study we assess the effect of vitamin D metabolites on CK in rat epiphyseal cartilage (Ep) and diaphyseal bone (Di). Female or male Wistar- derived rats were used either as intact or after gonadectomy (Ovx or cast respectively), and treatments started 2 weeks post surgery. Rats were injected daily for 1, 2 or 8 weeks with the less-calcemic vitamin D analogs CB 1093 (CB), J...

We examined the response of rat female pituitary at different metabolic stages to treatments with estrogenic compounds and vitamin D analogs. Immature or ovariectomized (Ovx) female rats, responded by increased creatine kinase specific activity (CK) to estradiol-17β (E2), genistein (G), daidzein (D), biochainin A (BA), quecertin (Qu), carboxy- G (cG), carboxy- BA (cBA) and raloxifene (Ral). The response was inhibited when Ral was injected together with the estr...