This study measured the sequelae of cholecalciferol (VD₃) therapy on ovarian functions in adult VD-replete rats (n = 48). The animals were distributed into the control and VD groups following estrous cycle synchronisation. The VD group received VD₃ injections for 4 weeks (600 IU/Kg; 3 times/week). Vaginal cytology and cycle durations were recorded throughout the study. Serum VD (25-OH VD), Ca²⁺, gonadotrophins (FSH & LH) and sex steroids (E2 & progesterone) were measured following euthanasia. Follicles and corpora lutea were counted in ovarian tissue sections. VD receptor, binding protein, Ca²⁺-sensing receptor and retinoid X receptor-α genes and proteins were measured by quantitative RT-PCR and immunohistochemistry. Serum VD, LH, E2 and progesterone levels were significantly higher, whereas FSH declined, in the VD group than controls. VD₃ therapy was also associated with markedly higher rates alongside shorter durations of estrous cycles than controls. While serum Ca²⁺ levels were equal between the study groups, they correlated directly with serum 25-OH VD. The numbers of small and medium size ovarian follicles were equal in both study groups, whereas large follicles and corpora lutea counts were significantly higher in the VD group. The mRNAs and proteins of targeted molecules also increased substantially in the VD group than controls. In conclusion, treating VD-sufficient female rats with supraphysiological VD₃ supplements was not associated with hypercalcaemia, and could contribute to ovarian functions by regulating the hypothalamic-pituitary-ovarian hormones and ovarian VD-related molecules. However, further studies are still needed to illustrate the clinical significance of VD₃ in female reproduction.

本研究测量了胆钙化醇 (VD ₃ ) 治疗对成年 VD 充足大鼠 ( n  = 48)卵巢功能的后遗症。在发情周期同步后将动物分配到对照组和VD组。VD组接受VD ₃注射4周（600 IU/Kg；3次/周）。在整个研究过程中记录阴道细胞学和周期持续时间。安乐死后测量血清 VD (25-OH VD)、Ca ²⁺、促性腺激素 (FSH & LH) 和性类固醇 (E2 & 孕酮)。在卵巢组织切片中计数卵泡和黄体。VD 受体，结合蛋白，Ca ²⁺-传感受体和类视黄醇 X 受体-α 基因和蛋白质通过定量 RT-PCR 和免疫组织化学进行测量。与对照组相比，VD 组的血清 VD、LH、E2 和孕酮水平显着升高，而 FSH 水平下降。与对照组相比，VD ₃治疗还与显着更高的发生率以及更短的发情周期持续时间相关。而血清 Ca ²⁺研究组之间的水平相等，它们与血清 25-OH VD 直接相关。两个研究组中小型和中型卵巢卵泡的数量相等，而 VD 组的大卵泡和黄体计数显着更高。与对照组相比，VD 组中靶分子的 mRNA 和蛋白质也显着增加。总之，用超生理性 VD ₃补充剂治疗 VD 充足的雌性大鼠与高钙血症无关，并且可以通过调节下丘脑 - 垂体 - 卵巢激素和卵巢 VD 相关分子来促进卵巢功能。然而，仍然需要进一步的研究来说明 VD ₃在女性生殖中的临床意义。