Zuogui Wan improves trabecular bone microarchitecture in ovariectomy-induced osteoporosis rats by regulating orexin-A and orexin receptor.

Objective: To investigate the protective effects of Zuogui Wan (ZGW) on bone loss induced by ovariectomy (OVX) and its mechanism via orexin-A and orexin receptors in the osteoporosis rat model.

Methods: Fifty Sprague-Dawley female rats were randomly divided into sham-operated (sham) group and four OVX subgroups. Rats subjected to sham and OVX were treated with the vehicle (OVX, 1 mL/100 g weight, n = 10), 17β-estradiol (E2, 50 μg*kg-1*d-1), and ZGW at the doses of 2.