Aronsson Patrik, Carlsson Thomas, Winder Michael, Tobin Gunnar
Department of Pharmacology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Neurourol Urodyn. 2014 Jun;33(5):550-7. doi: 10.1002/nau.22435. Epub 2013 May 29.
The search for new animal models to investigate both efferent and afferent levels of the micturition reflex, to better understand urinary dysfunctions, is of great importance. Therefore in this study we developed and characterized, by comparisons with a conventional whole bladder model, a novel in situ model.
The urinary bladder was carefully prepared and separated, via a midline incision, into two halves all the way to the urethra in pentobarbitone and medetomidine anesthetized male rats. The separated bladder halves (with no direct connection) were immobilized with ligatures to the underlying tissue. The tension could thereafter be recorded at one side, while the other half was occasionally stretched in order to evoke an afferent signal. Also, injections of ATP and methacholine and electric nerve stimulation were employed.
Ipsilateral stretch of 30 and 50 mN induced a force-dependent contractile response on the contralateral side. Moreover, electrical stimulation of efferent pelvic nerve fibers, and intravenous injections of methacholine and ATP, evoked dose-dependent contractions, resembling responses observed in the whole bladder model. Here, the threshold frequency at electrical stimulation of the efferent fibers was <2 Hz and the maximum response appeared at 10-20 Hz, while afferent stimulation had a threshold of 5-10 Hz with the maximum response at 40 Hz.
In the current study we show that stimulation of afferents at one side of the bladder induces, via impulses from the central nervous system, contractions from the other side. This novel model enables quantitative comparisons of changes occurring within the micturition reflex arc in bladder disorders. Neurourol. Urodynam. 33:550-557, 2014. © 2013 Wiley Periodicals, Inc.
寻找新的动物模型来研究排尿反射的传出和传入水平，以更好地理解排尿功能障碍，这具有重要意义。因此，在本研究中，我们通过与传统的全膀胱模型进行比较，开发并表征了一种新型的原位模型。
在戊巴比妥钠和美托咪定麻醉的雄性大鼠中，通过中线切口小心地制备膀胱，并将其一直分离到尿道，分成两半。分离的膀胱两半（无直接连接）用结扎线固定于下方组织。此后可在一侧记录张力，同时偶尔拉伸另一侧以诱发传入信号。此外，还采用了ATP和乙酰甲胆碱注射以及电神经刺激。
同侧30和50 mN的拉伸在对侧诱发了力依赖性收缩反应。此外，传出盆神经纤维的电刺激以及乙酰甲胆碱和ATP的静脉注射诱发了剂量依赖性收缩，类似于在全膀胱模型中观察到的反应。在此，传出纤维电刺激的阈值频率<2 Hz，最大反应出现在10 - 20 Hz，而传入刺激的阈值为5 - 10 Hz，最大反应出现在40 Hz。
在本研究中，我们表明刺激膀胱一侧的传入神经会通过中枢神经系统的冲动诱发另一侧的收缩。这种新型模型能够对膀胱疾病中排尿反射弧内发生的变化进行定量比较。《神经泌尿学与尿动力学》33:550 - 557，2014年。© 2013威利期刊公司。
