OBJECTIVETo establish a prostatic hyperplasia model with Beagle canines.

METHODSTwenty-four two-year-old male Beagle canines were divided into treatment and control groups at random and were administrated testosterone propionate (TP) through intramuscular injection two months after castration. Three treatment groups were given 0.8, 2.5 and 7.5 mg/kg TP respectively, and the control was given the same volume of vehicle. Two months later, half of the animals were killed and the serum and prostate were prepared. After the wet weight and volume of prostate were measured, the dihydrotestosterone (DHT) level of serum and prostate were detected with DHT radioimmunoassay (RIA) kit, and paraffine section from canine prostate was stained by the HE methods. Pictures were taken by digital camera under microscope, and all the pictures were analyzed by computer for epithelial cell height and acinar luminal area of prostate with micro image analysis software. The canine prostate volume was measured with ultrasonic diagnosis instrument before castration, at two months after castration and at two months after being given TP.

RESULTSThe ultrasonic results showed that the prostate volumes of all the canines were smaller at two months after castration than before castration (P < 0.05), and after having been administrated TP for two months, and the prostate volumes of all treatment groups were larger than those of the control group (P < 0.01). The wet weight of the prostate of the treatment group was higher than that of the control group (P < 0.05), and both had dose-dependent relationship. The DHT level of serum and prostate of the canines became higher with the increase of TP dose. The results of micro image analysis showed that the acinar luminal area of prostate was enlarged, and the epithelial cell height increased with larger dose of TP.

CONCLUSIONSIt is practicable to establish prostatic hyperplasia model in Beagle canines after two months of TP administration.