Smith Phillip P, Hurtado Eric, Smith Christopher P, Boone Timothy B, Somogyi George T
Scott Department of Urology, Baylor College of Medicine, Houston, Texas, USA.
Neurourol Urodyn. 2008;27(4):324-9. doi: 10.1002/nau.20512.
Rat cystometry is a common model used to investigate urinary storage and voiding function. The effect of cystometric instrumentation in rat studies might be a source of deviation from normal physiologic responses. We hypothesized that transurethral catheterization would produce obstruction-related changes, and that suprapubic catheterization would limit volume-related functions as well as disrupt normal urothelial sensory function. We investigated the influence of transurethral and suprapubic catheterization on storage and voiding in the rat model.
Three groups of female SD rats 250-300 g under urethane anesthesia were studied. Cystometric and pseudoaffective responses to physiologic voiding with and without suprapubic catheter placement, and cystometry via suprapubic and transurethral catheterization were studied.
In free-voiding animals, per-void volume was 1.8 +/- 0.2 ml with an average flow rate of 0.18 ml/sec, and intercontraction interval (ICI) 60 min. Suprapubic catheterization decreased the ICI and per-void volume consistent with capacity reduction. Suprapubic cystometry did not significantly alter parameters compared to voiding except for a shortened ICI. Bladder pressures and somatic responses were increased, and urine flow impaired by transurethral cystometry. Terazosin did not significantly improve voiding parameters.
Other than volume-related parameter changes probably related to surgical compromise of bladder capacity, suprapubic catheterization does not alter the cystometric and physiologic responses to voiding when compared to normal, uninstrumented voiding. Transurethral cystometry appears to be obstructive and may activate nociceptive reflexes. For this reason, whenever possible, urodynamic testing using the rat model should employ suprapubic catheterization.
大鼠膀胱测压是用于研究膀胱储尿和排尿功能的常用模型。膀胱测压仪器在大鼠研究中的影响可能是导致与正常生理反应产生偏差的一个原因。我们推测经尿道插管会产生与梗阻相关的变化，而耻骨上插管会限制与容量相关的功能，并破坏正常的尿路上皮感觉功能。我们研究了经尿道和耻骨上插管对大鼠模型中储尿和排尿的影响。
对三组体重250 - 300克、在氨基甲酸乙酯麻醉下的雌性SD大鼠进行研究。研究了在有或没有耻骨上插管情况下对生理性排尿的膀胱测压和假情感反应，以及通过耻骨上和经尿道插管进行的膀胱测压。
在自主排尿的动物中，每次排尿量为1.8±0.2毫升，平均流速为0.18毫升/秒，收缩间期（ICI）为60分钟。耻骨上插管使ICI和每次排尿量减少，这与容量减少一致。与排尿相比，耻骨上膀胱测压除了ICI缩短外，并未显著改变参数。膀胱压力和躯体反应增加，经尿道膀胱测压使尿流受损。特拉唑嗪并未显著改善排尿参数。
除了可能与膀胱容量手术受损相关的容量相关参数变化外，与正常的未插管排尿相比，耻骨上插管不会改变膀胱测压和排尿的生理反应。经尿道膀胱测压似乎具有梗阻性，可能会激活伤害性反射。因此，只要有可能，使用大鼠模型进行尿动力学测试时应采用耻骨上插管。
