Abstract: Objective To establish observation the methods for microcirculation of uterine wall and mesometrium in rats. Methods Thirty female SD rats were anesthetized through intraperitoneal injection with 2% pentobarbital sodium(30 mg/kg). After routine abdomen disinfection, the rats were fixed in supine position, with two lower limbs abducted maximally. A longitudinal cut was made whose length was 1.5~2 cm and 0.5cm outside of abdomen midline. We made blunt dissection of subcutaneous tissue and draw one side of uterus and its ligament. Put uterus and the ligament on microcirculation calorstat which was in transparent plexiglass groove with water controlled temperature of 37.5℃. The uterus and ligament were fixed and flattened on the pillai, a small plexiglass pillar which was 20 mm width and 15 mm height ,used for observation. The tissues were kept moist with 37℃ Riger's solution. The microcirculation of uterine wall and mesometrium were observed and calculated capillary parameter value with the use of cold light source as an external light. The microcirculation of uterus of 15 rats were observed 30 min post 2 IU (international Unit) oxytocin IV injection. Results The diameter of arteriole in mesometrium of rats was 8~15 μm, while the diameter of its microvein was 25~45 μm, the diameter of arteriole of uterine wall was 6~12 μm, and while the diameter of its microvein was 15~30 μm. After the injection of oxytocin, the diameter of arteriole of mesometrium and uterine wall decreased 38.24% and 25.14% respectively, which has significantly difference comparing with normal group (P<0.05, P<0.05). Conclusion The anatomical position of mesometric capillary of rats is obvious and easy for dissection. The blood vessels of microcirculation are clear and have abundant blood flow, which are benefit for human disease prevention and medicine study.

Key words: Uterus, Uterine wall, Mesometrium, Microcirculation, Observation method, Rats