Pathophysiology of interstitial cystitis

Interstitial cystitis/bladder pain syndrome is a chronic pain syndrome whose causes remains elusive with no generally accepted treatment. A hallmark of functional pain syndromes such as interstitial cystitis/bladder pain syndrome is pain in the absence of demonstrable pathology of the viscera or associated nerves. Patients with chronic pain experience a greater impairment in quality of life than healthy controls. In addition, interstitial cystitis/bladder pain syndrome symptoms can frequently overlap with other conditions including irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, anxiety disorders, and a number of other syndromes not directly related to the urinary bladder. Because of the complex pathophysiology, a number of animal models have been studied over the years to better understand mechanisms underlying patient symptoms. These models can include: bladder centric, complex mechanisms and psychological and physical stress models. Such animal models can aid in the investigation of aspects of interstitial cystitis/bladder pain syndrome that cannot be pursued in humans as well as to develop and test potential therapies. In addition, the search for urinary factors that may be a cause of interstitial cystitis/bladder pain syndrome has resulted in the discovery of a number of potential targets that could serve as predictive biomarkers which can aid in early diagnosis and treatment of this chronic disorder.     

睾丸及附睾炎性病变体表牵涉痛与穴位敏化形成的联系

目的:观察睾丸及附睾炎性病变患者体表牵涉痛分布区与治疗该类疾病相关穴位的关系,通过动物实验进一步对比相关内脏器官体表敏化区与穴位的关系。方法:临床研究部分将93例睾丸、附睾炎患者临床体查确定的体表痛敏点进行总结分析,将其分布部位与临床治疗该类疾病常用穴位进行对比;动物实验部分观察雄性SD睾丸炎模型大鼠(n=8)、对照组(n=3)注射伊文思蓝(Evans Blue)后体表渗出点,与临床痛敏点和相关穴位对比。结果:临床观察93例睾丸、附睾炎患者体表痛敏点大多分布在下腹部及下肢内侧,腰部及会阴部也有部分分布,痛敏点分布范围与大部分治疗该类疾病常用穴位所处位置在同一区域,并有部分重叠;动物实验观察到体表Evans Blue渗出点与临床痛敏点分布情况高度相似。结论:睾丸、附睾炎性病变引发的体表痛敏点多数与治疗该类疾病的相关穴位所处位置重叠或邻近,提示这些疾病状态下的体表敏化点可能是穴位形成的主要原因。     

Local and generalized sensitization of thermally evoked defensive behavior in caterpillars

In addition to camouflage and chemical toxicity, many caterpillars defend themselves against predators with sudden sharp movements. For smaller species, these movements propel the body away from the threat, but in larger caterpillars, such as the tobacco hornworm, Manduca sexta, the movement is a defensive strike targeted to a noxious stimulus on the abdomen. Previously, strikes have been studied using mechanical stimulation like poking or pinching the insect, but such stimuli are hard to control. They also introduce mechanical perturbations that interfere with measurements of the behavior. We have now established that strike behavior can be evoked using infra-red lasers to provide a highly localized and repeatable heat stimulus. The latency from the end of an effective stimulus to the start of head movement decreased with repeated stimuli and this effect generalized to other stimulus locations indicating a centrally mediated component of sensitization. The tendency to strike increased with two successive subthreshold stimuli. When delivered to different locations or to a single site, this split-pulse stimulation revealed an additional site-specific sensitization that has not previously been described in Manduca. Previous work shows that strong stimuli increases the effectiveness of sensory stimulation by activating a long-lasting muscarinic cation current in motoneurons. Injection of muscarinic cholinergic antagonists, scopolamine methyl bromide or quinuclidinyl benzilate, only decreased the strike probability evoked by paired stimuli at two locations and not at a single site. This strongly suggests a role of muscarinic acetylcholine receptors in the generalized sensitization of nociceptive responses in caterpillars.