This study was conducted to assess the effectiveness of a diet contained fresh anchovies and calcitriol supplementation for 6 weeks to prevent osteoporosis in ovariectomized rats. Fifteen Wistar rats aged 8 weeks were divided randomly into 3 groups (normal/K, ovariectomized/Ov, andovariectomized + calcitriol/OVD), 5 mice each. Group K and Ov rats were fed with fresh anchovies, while the OVD group was fed with freshanchovies + calcitriol. At the age of 15 weeks, all mice were done for euthanasia, then left femur was collected for immunohistochemistryexamination of tartrate resistant acid phosphatase5b (TRAP5b). The detection of (TRAP5b) was conducted using a monoclonal ant ibody antiTRAP5b, and detected using a streptavidin-biotin. The results showed that the metaphysis part of distal femur bone of mice group K, Ov, andOVD were positive TRAP5b stained with brown color on trabecular bone in bone marrow cavity and trabecular spiculum surface, but rats ingroup K and Ov had extensive bone marrow cavity and normal trabecular spiculum, whereas OVD group showed bone marrow cavity dilation,accumulation of adipocytes in the bone marrow cavity, and shorter the spiculum of trabeculae. It can be concluded that fresh anchovies diet andcalcitriol supplementation for 6 weeks are not effective in preventing osteoporosis in ovariectomized rats.Key words: calcitriol, femur, ovariohisterectomy

Penelitian ini dilakukan untuk mengaji respons metafisis tulang femur distalis tikus ovariektomi yang mengonsumsi suplemen kalsitriol selama enam minggu. Lima belas tikus Wistar umur delapan minggu, secara acak dibagi tiga kelompok (normal/N, ovariektomi/Ov, dan ovariektomi + kalsitriol/OvD) masing-masing 5 tikus. Tikus kelompok N dan Ov diberi pakan standar, sedangkan tikus kelompok OvD diberi pakan standar + kalsitriol. Pada umur 14 minggu, tikus dimasukkan kandang metabolik individu untuk studi balan. Pada hari 4-7 studi balan, setiap hari sisa pakan, urin, dan feses dikoleksi untuk pemeriksaan Ca. Pada akhir penelitian, tikus dieutanasia, tulang femur kanan diambil pemeriksaan histopatologis dengan pengecatan hematoksilin dan eosin. Hasil penelitian menunjukkan bahwa konsumsi Ca dan retensi Ca pada tikus OvD tidak berbeda signifikan meskipun cenderung meningkat, sedangkan ekskresi Ca dalam feses dan urin meningkat sangat signifikan (P<0,01). Metafisis tulang femur distalis tikus kelompok OvD terlihat zona spikulum tulang trabekula lebih pendek dan berbentuk irreguler, dan rongga sumsum tulang didominasi jaringan adiposit. Dari hasil penelitian dapat disimpulkan bahwa suplementasi kalsitriol selama enam minggu pada tikus ovariektomi menyebabkan osteoporosis pada metafisis tulang femur distalis.