Kawakami E, Tsutsui T, Shimizu M, Orima H, Fujita M, Ogasa A
Department of Reproduction, Nippon Veterinary and Animal Science University, Tokyo, Japan.
Int J Androl. 1995 Oct;18(5):248-55.
Five beagles out of 11 dogs aged 7-10 years with benign prostatic hypertrophy (BPH) were implanted subcutaneously with pellets of the synthetic anti-androgen chlormadinone acetate (CMA) at a dose of 10 mg/kg bodyweight. The remaining six dogs (one beagle and five mongrel dogs) underwent bilateral orchidectomy. Changes in prostatic volume, histological findings in the prostate and the testis, and peripheral plasma levels of LH, testosterone and oestradiol-17 beta (E2) were assessed up until 24 and 4 weeks after CMA-implantation and orchidectomy, respectively. Measurements of the size of the prostate and biopsies of the prostate were performed by laparotomy. Mean prostatic volume had decreased to 71% and 41%, respectively, of its pretreatment volume, by 4 weeks after CMA-implantation and orchidectomy, and was 49% and 47%, respectively, of pretreatment volume at 12 and 24 weeks after CMA-implantation. The clinical signs of BPH, e.g. haematuria, resolved within 2 weeks after either treatment. When the prostate was examined histologically 4 weeks after either treatment, hardly any evidence of active secretion (e.g. glandular epithelium projecting markedly into the lumen), was observed in CMA-implanted dogs, alveolar diameter and height of the glandular epithelium had decreased markedly and the glandular lumen had become very small in the orchidectomized dogs. By 12 weeks after CMA-implantation, degenerative and atrophic glands were observed in the prostate nearly the same as at 4 weeks after orchidectomy. In the testis the number of germ cells in the seminiferous tubules decreased markedly after CMA-implantation. The mean level of plasma LH at 4 weeks after orchidectomy had increased to 14.9 ng/ml, twice the value before operation. The mean levels of plasma testosterone and E2 at 4 weeks after CMA-implantation had decreased to 0.7 ng/ml and 9 pg/ml from 1.5 ng/ml and 15 pg/ml, the values before treatment, respectively. CMA-implantation resulted in poor semen quality. The results indicate that CMA-implantation at a dose of 10 mg/kg results in the same prostate-shrinking effect as orchidectomy.
11只年龄在7至10岁患有良性前列腺增生（BPH）的犬中，5只皮下植入了剂量为10毫克/千克体重的合成抗雄激素醋酸氯地孕酮（CMA）丸剂。其余6只犬（1只比格犬和5只杂种犬）接受了双侧睾丸切除术。分别在CMA植入和睾丸切除术后24周和4周，评估前列腺体积的变化、前列腺和睾丸的组织学发现以及外周血中促黄体生成素（LH）、睾酮和雌二醇-17β（E2）的水平。通过剖腹术测量前列腺大小并进行前列腺活检。CMA植入和睾丸切除术后4周，前列腺平均体积分别降至治疗前体积的71%和41%，CMA植入后12周和24周分别为治疗前体积的49%和47%。两种治疗后2周内，BPH的临床症状如血尿均得到缓解。两种治疗后4周对前列腺进行组织学检查时，CMA植入犬几乎未观察到任何活跃分泌的迹象（如腺上皮明显突入管腔），睾丸切除犬的腺泡直径和腺上皮高度明显减小，腺腔变得非常小。CMA植入后12周，前列腺中观察到的退行性和萎缩性腺与睾丸切除术后4周几乎相同。CMA植入后，睾丸生精小管中的生殖细胞数量明显减少。睾丸切除术后4周，血浆LH平均水平升至14.9纳克/毫升，是手术前值的两倍。CMA植入后4周，血浆睾酮和E2的平均水平分别从治疗前的1.5纳克/毫升和15皮克/毫升降至0.7纳克/毫升和9皮克/毫升。CMA植入导致精液质量较差。结果表明，剂量为10毫克/千克的CMA植入产生的前列腺缩小效果与睾丸切除术相同。
