Establishment of prostate urethral re-epithelialization model with Chinese rural canine by 2 μm laser vaporization resection

Abstract

Objective To establish a prostate urethral re-epithelialization model with Chinese rural canine by 2 μm laser vaporization resection. Methods We used 2 μm laser to vaporiz prostate of 15 uncastrated male Chinese rural canines from March to April in 2016.These canines mean age was (6.3±0.6) years(ranging 5-7 years), and weight was (20.5±1.3) kg(ranging 18-22 kg). We began to surgery in which we saw the protruding part of the prostate in urethra, and narrow prostate urethra after a successful anesthesia by intraperitoneal injection of chloral hydrate. The operation time, anesthesia time, survival rate, first time to drink water, first time to feed, first time to stand, first time to defecate, the time when canine bladders rinse became clear, wound healing time were recorded. After 3 days, 1 week, 2 weeks, 3 weeks and 4 weeks, we randomly select 3 canines to observe regeneration of prostate urethra wound under cystoscope. After surgery, the bladder, prostate and prostate distale urethra were removed to make specimen and measure the diameter size of prostate. The HE staining and immunohistochemistry was performed in each sample. Results The experimental operation time was (70.5±18.3) min (ramging 50-90 min). The average anesthesia time was (120.1±21.1) min (ranging 95-145 min). The survival rate was 100%.In post surgery duration first standing time, first eating time , first drinking water time, first defecation time were (6.5±1.8)h, (10.3±2.1)h, (23.7±5.6)h, (26.3±3.1)h, respectively. The time when canine bladders rinse became clear and wound healing time were (5.2±1.6)d, (8.7±1.5)d respectively. Cystoscopy observated that the wound was covered by pale necrotic tissue 3 d and 1 week after operation, covered by epithelium 2 weeks after operation, covered by more thicker epithelium 3 weeks after operation, covered by epithelium which color was close to normal urothelium 4 weeks after operation. HE staining observated that the wound wasn't covered by epithelium 3 d after operation, partial wound was covered by flaky single or 2-3 cubic regenerated epithelial 1 week after operation, all wound was covered by epithelial which was lack of polar 2 weeks after operation, wound was covered by polarity epithelium which was thicken to 5-6 layer and observated a little umbrella cells on the surface 3 weeks after operation, wound was covered by polarity epithelium which was thicken to 5-6 layer and observated much umbrella cells on the surface 4 weeks after operation. Immunohistochemical staining observated that urinary spot protein from the wound or epithelium was negative 3 d, 1 and 2 weeks after operation, urinary spot protein from the part of epithelium was positive 3 weeks after operation, and urinary spot protein from all epithelium was positive 4 weeks after operation. Conclusion It is feasible to establish prostate urethral re-epithelialization model in the Chinese rural canine by 2 μm laser vaporization resection of the prostate. Key words: Laser; Vaporization resection of prostate; Re-epithelialization