Inflammation and enhanced nociceptive responses to bladder distension produced by intravesical zymosan in the rat

BACKGROUND: Mycotic infections of the bladder produce pain and inflammatory changes. The present study examined the inflammatory and nociceptive effects of the yeast cell wall component, zymosan, when admininstered into the urinary bladder in order to characterize this form of bladder sensitization. METHODS: Parametric analyses of the time-course (0–48 hr) and concentration (0–2% solutions) variables associated with intravesical zymosan-induced bladder inflammation were performed in female rats. Plasma extravasation of Evan's Blue dye was used as a measure of tissue inflammation. Cardiovascular and visceromotor responses to urinary bladder distension were used as measures of nociception. RESULTS: Zymosan-induced bladder inflammation, as indexed by plasma extravasation of Evan's Blue, was significantly greater in rats treated with either 1 or 2% solutions as compared to either 0.1 or 0.5% zymosan solutions. In time-course studies (1 – 48 hr post-treatment), 1% zymosan-induced inflammation progressively increased with time following administration, was greatest at 24 hr and began to normalize by 48 hr. In the studies of inflammation-induced changes in nociception, arterial blood pressure (ABP) and visceromotor responses to graded distension of the urinary bladder were significantly increased relative to controls 24 hr after zymosan administration. CONCLUSION: These studies provide important time-course and solution concentration parameters for studies of zymosan-induced inflammation of the bladder and suggest utility of this model for the study of bladder-related pain

Inflammation and enhanced nociceptive responses to bladder distension produced by intravesical zymosan in the rat

Abstract Background Mycotic infections of the bladder produce pain and inflammatory changes. The present study examined the inflammatory and nociceptive effects of the yeast cell wall component, zymosan, when admininstered into the urinary bladder in order to characterize this form of bladder sensitization. Methods Parametric analyses of the time-course (0–48 hr) and concentration (0–2% solutions) variables associated with intravesical zymosan-induced bladder inflammation were performed in female rats. Plasma extravasation of Evan's Blue dye was used as a measure of tissue inflammation. Cardiovascular and visceromotor responses to urinary bladder distension were used as measures of nociception. Results Zymosan-induced bladder inflammation, as indexed by plasma extravasation of Evan's Blue, was significantly greater in rats treated with either 1 or 2% solutions as compared to either 0.1 or 0.5% zymosan solutions. In time-course studies (1 – 48 hr post-treatment), 1% zymosan-induced inflammation progressively increased with time following administration, was greatest at 24 hr and began to normalize by 48 hr. In the studies of inflammation-induced changes in nociception, arterial blood pressure (ABP) and visceromotor responses to graded distension of the urinary bladder were significantly increased relative to controls 24 hr after zymosan administration. Conclusion These studies provide important time-course and solution concentration parameters for studies of zymosan-induced inflammation of the bladder and suggest utility of this model for the study of bladder-related pain.</p

Protest Against Waste Contamination in the ‘Land of Fires’: Psychological Antecedents for Activists and Non-activists

The ‘Land of Fires’ is a district in Italy characterized by illegal waste disposal, waste burning, and citizen protests over contamination. This study investigates the relevance of several psycho-social factors that predict citizens' intention to protest, taking into account different research traditions. In addition, we hypothesize the effect of protest antecedents to be moderated by past participation behaviour (i.e. the level of activism). Hence, our study is a first attempt to explore the effect of protest antecedents as a function of the individual level of activism through a cross-sectional survey study (N = 306). The results show significant effects of collective identity, sense of injustice, costs of protest, and perceived risk (cognitive dimension) on intention to protest. The effects of collective efficacy and perceived risk (affective dimension) are moderated by participants' level of activism, and these effects are significant only for non-activists. The relevance of this new approach is discussed, as well as practical implications and possible further developments. Copyright © 2016 John Wiley & Sons, Ltd