Abstract:

Objective To investigate the feasibility of establishment of animal model of interstitial cystitis by protamine sulfate plus lipopolysaccharide. Methods Thirty female SD rats were divided into experiment group, cyclophosphamide group and control group, with 10 rats in each group. Transurethral bladder perfusion of 10 mg/mL protamine sulfate plus 750 μg/mL lipopolysaccharide was performed in experiment group, intraperitoneal injection of 100 mg/kg cyclophosphamide was conducted in cyclophosphamide group, and PBS solution perfusion was administered in control group. Mononuclear inflammatory cells in bladder tissues were counted with HE staining, degranulated mast cells were counted with special staining, and the urine mass concentrations of histamine in groups were measured. Results A large number of mononuclear inflammatory cells and degranulated mast cells in bladder tissues were observed in experiment group, a large number of mononuclear inflammatory cells and a small number of degranulated mast cells in bladder tissues were found in cyclophosphamide group, and a small number of mononuclear inflammatory cells and degranulated mast cells in bladder tissues were detected in control group. The numbers of mononuclear inflammatory cells per visual field in experiment group (76.5±9.8) and cyclophosphamide group (69.3±6.9) were significantly larger than that in control group (16.5±9.8)(P<0.05). The number of degranulated mast cells per visual field in experiment group (8.4±3.1) was significantly larger than those in cyclophosphamide group (1.2±1.6) and control group (0.7±0.3)(P<0.05). The urine mass concentration of histamine in experiment group [(58.5±10.3) pg/mL] was significantly higher than those in cyclophosphamide group [(11.9±2.4) pg/mL] and control group [(8.9±3.2) pg/mL](P<0.05). Conclusion The animal model of interstitial cystitis established by 10 mg/mL protamine sulfate plus 750 μg/mL lipopolysaccharide is in line with the pathophysiological characteristics of interstitial cystitis, and the way of establishment is simple and reliable.

Key words: protamine sulfate, lipopolysaccharide, interstitial cystitis, animal model