A Trial Study of Propranolol and Zhigancao Decoction on the Central Depressant and Anti-osteoporosic Action in Ovariectomized Rats

Objective： This study was originally designed to observe the effects of propranolol （a β-blocker） and Zhigancao Decoction （炙甘草汤 ZGCD） on bone mass in ovariectomized rats. Methods： Thirty-eight female Sprague-Dawley rats were divided into four groups initially, a sham-operated group （Sham, n=7）, a model ovariectomized （OVX） group （Model, n=7）, a propranolol group （Pro, n=12） and a ZGCD group （ZGCD, n=12）. After 15 weeks of treatment, the expected effects were not found. In order to verify the situations of the experiment, we modified the study by administering calcitonin to a subgroup of the tested Pro and ZGCD rats. Results： The Pro and ZGCD treatments showed decreased heart rate and plasma norepinephrine level, but neither an increased bone mass nor any bone metabolism differences from the model rats were found. However, the OVX-induced bone loss was prevented by the sequent treatment of calcitonin. Conclusions： The results provide no evidence that the β-blocker propranolol may stimulate bone formation, and do not iustify its use for clinical treatment of osteoporosis.

Effect of acupuncture at acupoint of Shenshu (BL 23) on the bones of ovariectomized rats

OBJECTIVE： To investigate the effect of acupuncture at acupoint of Shenshu （BL 23） in ovariectomized rats and sham-operated rats. METHODS： Female Sprague-Dawley rats were divided into the following four groups （n = 12 each）： sham operation only （Sham）, sham operation with acupuncture （Sham ＋ ACP）, ovariectomy only （OVX）, and ovariectomy with acupuncture （OVX ＋ ACP）. Operations were performed at the 9th week of age. Acupuncture of Shenshu （BL 23） was started at the 1 lth week of age and conducted 3 times per week until the 26th week of age. RESULTS： Among ovariectomized rats, the acupuncture-treated rats had significantly lower body weights and cross-linked N-telopeptide of type 1 collagen levels in the urine after 3 weeks of acu- puncture treatment, higher bone mineral density of the lumbar vertebra after 7 weeks, and smaller trabecular separation of the sixth lumbar vertebra, measured by micro-computed tomography, after 17 weeks than control rats. These effects were not observed in sham-operated rats. Blood concentrations of estradiol were significantly higher in the OVX ＋ ACP group than in the untreated group. Acupuncture treatment increased plasma testosterone levels in sham-operated rats, while this increase was not observed in OVX rats. CONCLUSION： Acupuncture of Shenshu （BL 23） prevents bone loss and structural changes by sup- pressing bone resorption.