The Role of the Mucosa in the in vitro Changes in Guinea Pig Bladder Function Which Occur after Sensitization with Ovalbumin

Abstract

Bladder strips from sensitized guinea pigs respond to ovalbumin challenge with a contraction accompanied by release of histamine, prostaglandin, and leukotriene. Histamine and prostaglandin release occurs preferentially from the bladder mucosa, while leukotrienes are released by the smooth muscle. This study investigated the effects of removal of the bladder mucosa on contractile responses of strips from control and sensitized guinea pigs to electrical stimulation and to contractile agonists. Removal of the mucosa potentiated the contractile response to electrical stimulation at low voltages and pulse durations. The presence of ovalbumin had no effects on the response to electrical stimulation. Removal of the mucosa had no effect on the contractile responses of bladder strips to bethanechol, histamine, KC1, or ovalbumin, although after correction for the decreased strip mass after mucosa removal there was a tendency for the responses to increase. We conclude that the responsiveness of bladder strips from sensitized guinea pigs to ovalbumin challenge results primarily from effects which occur within the smooth muscle.

Characterization of the motor inhibitory role of colonic mucosa under chemical stimulation in mice

“…Thus, the strips without mucosa responded to electrical field stimulation (EFS), bethanechol, ATP, and KCl significantly greater than the strips with mucosa, which suggest an inhibitory role of the urothelium in the control of bladder contractility (13). This is in agreement with another study performed by the same group in guinea pig bladder (12). Although the urothelium differs from the colonic mucosa in its absorptive properties, both layers contact with smooth muscle layers whose activation propels contents.…”

Tissue Distribution of Human AKR1C3 and Rat Homolog in the Adult Genitourinary System

“…To date, little is known about the role of AKR1C3 in the urothelium. The urothelium has been shown to be the main source of PGs within the bladder (Krasnopolsky et al 1995), and it has been The Journal of Histochemistry & Cytochemistry AKR1C3 in the Genitourinary System suggested that these PGs could be related to a stretch sensing role during bladder filling (Azadzoi et al 2004;Schroder et al 2004;de Jongh et al 2007). Alternate roles for AKR1C3, and its rat homolog, in the bladder could be for the creation of a watertight barrier for confining urine and as a possible regulator controlling the inflammatory effects of urine (Oleksiewicz et al 2005).…”

The role of the mucosa in modulation of evoked responses in the spinal cord injured rat bladder

“…In contrast to mucosa‐dependent inhibition, removal of the mucosa has also been shown to decrease the contractile response to muscarinic receptor stimulation, electrical field stimulation, and ATP, or to have no effect on the response to electrical field stimulation, carbachol, and KCl in the rat bladder. Similarly, in the guinea pig, the presence of the mucosa did not affect (or slightly increased) the response to histamine, bethanechol, KCl, and electrical stimulation . Moreover, a non‐adrenergic, non‐nitrergic, non‐prostanoid relaxant agent that does not originate from the mucosa was reportedly released by stimulation of muscarinic receptors in the detrusor, suggesting an inhibitory factor may also be produced by bladder tissue during contraction …”