Stereological comparison of intraprostatic injection of alcohol and bleomycin with finasteride gavages in rats.

INTRODUCTION: Resection of the prostate is one of the standard surgical treatments for symptomatic Benign Prostatic Hyperplasia (BPH). To evaluate minimally invasive treatments, intraprostatic injections of ethanol and bleomycin were compared with oral finasteride administration in rats with BPH.

MATERIAL AND METHODS: The rats were divided into six groups. The control rats received no BPH/no treatment. BPH was induced using injections of testosterone (2 mg/day/rat for 4 weeks) in groups II-VI. After 4 weeks, Group II received no treatment while Group III received oral finasteride (10 mg/kg/day). Moreover, Groups IV-VI received a single injection of ethanol (95%), bleomycin (5 mg/kg) and normal saline 25 mm3 in each ventral lobe of the prostate respectively. Two weeks after the injections, the ventral lobes underwent a quantitative stereological study.

RESULTS: The volume of the ventral lobes, glandular epithelium, fibromuscular tissue and microvessles increased by 1.7, 3.1, 2.4 and 1.6 times in BPH rats respectively (P <0.01). Alcohol or bleomycin injection in PBH rats induced drastic recession of the increased volume of the ventral lobe, glandular epithelium and fibromuscular tissue (P <0.01). Regarding the BPH+alcohol group, the glandular epithelium volume restored to the normal values of the control rats (P <0.01). BPH+finasteride also incited an atrophic change in the volume of the whole prostate and glandular epithelium, but not the fibromuscular tissue and microvessels (P <0.01).

CONCLUSIONS: Injection of alcohol and bleomycin (approximately 10% of the volume of ventral prostatic) as well as consuming finasteride can induce a reduction of 1/3, 1/4 and 1/5 in the hypertrophied gland respectively.