Chronic psychological stress enhances nociceptive processing in the urinary bladder in high-anxiety rats

Abstract

This study sought to determine whether acute and/or chronic psychological stress produce changes in urinary bladder nociception. Female Sprague-Dawley (SD; low/moderate anxiety) or WistarKyoto (WK; high-anxiety) rats were exposed to either an acute (1 day) or a chronic (10 days) water avoidance stress paradigm or a sham stress paradigm. Paw withdrawal thresholds to mechanical and thermal stimuli and fecal pellet output, were quantified at baseline and after the final stress or sham stress exposure. Rats were then sedated, and visceromotor responses (VMRs) to urinary bladder distension (UBD) were recorded. While acute stress exposure did not significantly alter bladder nociceptive responses in either strain of rats, WK rats exposed to a chronic stress paradigm exhibited enhanced responses to UBD. These high-anxiety rats also exhibited somatic analgesia following acute, but not chronic, stress. Furthermore, WK rats had greater fecal pellet output than SD rats when stressed. Significant stress-induced changes in nociceptive responses to mechanical stimuli were observed in SD rats. That chronic psychological stress significantly enhanced bladder nociceptive responses only in high-anxiety rats provides further support for a critical role of genetics, stress and anxiety as exacerbating factors in painful urogenital disorders such as interstitial cystitis (IC).

Repeated variate stress in male rats induces increased voiding frequency, somatic sensitivity, and urinary bladder nerve growth factor expression

“…Thus future studies should be pursued in anesthetized rats where potential effects of the outlet including the urethra and EUS can be evaluated after RVS. RVS-induced increases in voiding frequency are similar to other reports regarding several other animal models of stress including social defeat (4,15,46,74), nontraumatic immobilization/restraint (11,74), and WAS (14,54,62). We suggest that the 7-day RVS model has several advantages compared with other stress models.…”

“…Therefore, patients diagnosed with IC/BPS and other functional urinary tract disorders may have abnormalities in the HPA axis, and stress could contribute to bladder symptoms, including frequency, urgency, and/or pain, reported by these patient populations (47). The pathophysiology underlying stress-induced effects on micturition reflex function remain undetermined.The most well-established animal models of stress used to examine effects on urinary bladder structure and function include the resident-intruder model (15,22,74), immobilization stress (10, 11), water avoidance stress (WAS) (14,54,55,62), and electrical footshock (7,55). Although these stress paradigms produce bladder dysfunction and target tissue (i.e., urinary bladder) abnormalities similar to conditions like IC/BPS, the data in some cases are conflicting, and the stress models used in these studies may not be relevant to the variety of life stressors experienced by humans on a daily basis.…”

Genotype-dependent responsivity to inflammatory pain: A role for TRPV1 in the periaqueductal grey

“…In the chronic constriction injury model of neuropathic pain, WKY rats exhibited enhanced mechanical allodynia when compared to the Wistar rats (Zeng et al, 2008). Studies have also reported that hyperalgesia is exacerbated upon application of a water avoidance stress paradigm in WKY rats (Robbins et al, 2007).…”

Sudan kaçınma stresi uygulanmış erkek sıçan mesanesinde oksitosin etkisi: Işık ve elektron mikroskobik inceleme

“…SKS uygulanan grupta serum kortizol seviyesinde istatistiksel olarak anlamlı bir artış tespit edildiğinden, çalışmamızda kullandığımız kaygı stres modelinin çalışan ve geçerli bir model olduğu gösterilmiştir. Stresin ağrılı bir mesane hastalığı olan İS'in patofizyolojisinde önemli bir rol oynadığı birçok klinik ve deneysel çalışmada gösterilmiştir (3,4). SKS uygulanmış dişi sıçan mesane dokusuna ait ışık mikroskobik incelemelerde, lamina propriyada polimorf nüveli lökosit infiltrasyonu, ürotelyum hücrelerinde hasar, GAG tabakasında düzensizlik ve granüllü ve degranüle olmuş mast hücre artışı izlenmiştir (17,21,22).…”

“…Oksitosin grubuna (OT) 5 gün subkutan (sc) 5 µg/kg oksitosin uygulanmıştır. 4. Kronik Stres +Oksitosin grubuna (KS+OT) kronik stres boyunca 5μg /kg oksitosin sc uygulanmıştır.…”