Kohki tea protects the rabbit bladder from ischemia/reperfusion-induced contractile dysfunction.

Objectives: Results of several studies indicated that ischemia/reperfusion is an etiological factor in obstructive bladder dysfunction. Kohki tea pretreatment was shown to reduce the dysfunctions induced by partial outlet obstruction in rabbits. The current study was designed to determine if pretreatment of rabbits with Kohki tea could prevent the contractile dysfunctions induced by bilateral ischemia followed by reperfusion.

The effect of low-dose estrogen therapy on ovariectomized female rabbit bladder.

Objectives: To determine whether low-dose estrogen supplementation is as effective as high-dose supplementation in increasing bladder contractile function and mediating bladder hypertrophy and angiogenesis.

Methods: Sixteen New Zealand white female rabbits were separated into four groups of 4 rabbits each. Group 1 served as the control, and groups 2 to 4 underwent ovariectomy.

Free radical damage as a biomarker of bladder dysfunction after partial outlet obstruction and reversal.

Objective: To investigate the use of free-radical generation as a result of protein carbonylation and nitrotyrosination to characterize the level of bladder dysfunction after partial bladder outlet obstruction (PBOO) and reversal.

Materials And Methods: We surgically created PBOO in male New Zealand White rabbits; after 4 weeks of PBOO, one group of six rabbits was assessed, while the PBOO was relieved in two additional groups of six rabbits each that were assessed at 4 and 8 weeks after relieving the PBOO. Six sham-operated rabbits served as controls.

Effects of L-arginine and L-NAME on chronic partial bladder outlet obstruction in rabbit.

Nitric oxide (NO) is synthesized from L-arginine by nitric oxide synthase (NOS). NOS can be inhibited by NG-nitro-L-arginine methyl ester (L-NAME) and stimulated by supplementing the diet with L-arginine. The aim of this study was to investigate the influence of NOS activity on the response of rabbits to chronic partial bladder outlet obstruction (PBOO).

Effect of letrozole on urinary bladder function in the female rabbit.

Objective: To investigate the effect of letrozole (a potent aromatase inhibitor that effectively inhibit the synthesis of oestrogen) on bladder contraction with changes in morphology and biochemistry.

Materials And Methods: Sixteen female New Zealand white rabbits were separated into four equal groups; groups 1-3 were given oral letrozole for 1, 2 and 3 weeks, and group 4 was given saline and served as the control group. At the end of the medication period each rabbit was anaesthetized and the bladder muscle strips were used for contractile, histological and biochemical studies.

Effect of age on the response to short-term partial bladder outlet obstruction in the rabbit.

Objective: To compare the physiological and structural changes after short-term partial bladder outlet obstruction (PBOO) in young and old rabbits, as PBOO results in marked contractile and histological alterations in the bladder.

Materials And Methods: In all, 20 young (7-8-week-old) and 20 old (2 years old) male rabbits were divided into four subgroups of five each (four obstructed and one sham control rabbit). The rabbits in the groups were evaluated after 1, 3, 7 and 14 days of PBOO, respectively.

Novel biomarkers of bladder decompensation after partial bladder obstruction.

Aims: Partial bladder outlet obstruction (PBOO) results in marked contractile, biochemical, and histological alterations in the bladder. Our aim was to determine the time course of progressive PBOO in the rabbit and to find parameters that marked the shift to decompensation.

Materials And Methods: Twenty-four rabbits were subjected to 1, 2, 4, and 8 weeks of PBOO.

Long term partial bladder outlet obstruction induced contractile dysfunction in male rabbits: a role for Rho-kinase.

Aims: In this study we examined the expression of Rho-kinase (ROK) isoforms in rabbit detrusor smooth muscle during the progression of partial bladder outlet obstruction and correlated them with the time course of obstruction.

Methods: Detrusor samples were obtained from bladders after 1, 2, 4, and 8 weeks of obstruction and also sham operated control rabbits. Contractile responses to field stimulation (FS) and also the smooth muscle (SM) to collagen ratio were determined in isolated bladder strips.

The effect of maturation and age on oestrogen-induced functional hypertrophy of the female rabbit bladder.

Objective: To evaluate the effect of maturation and ageing on oestrogen-induced functional hypertrophy of the female rabbit bladder.

Materials And Methods: Twenty female rabbits were separated into two groups of 10 each by age, young (immature) and old rabbits and each age group was subdivided into three subgroups. The rabbits in subgroup 1 were controls, subgroup 2 were ovariectomized (Ovx) and subgroup 3 were Ovx and received 17-beta oestradiol (1 mg/kg/day) by a subcutaneous slow-release tablet implant.

The effect of intravesical ketoprofen on acetylcholine-evoked urinary bladder contractility and detrusor overactivity in the anesthetized rabbit model.

Intraurethral procedures such as the transurethral resection of the prostate can generate detrusor overactivity and bladder irritability. The rabbit model of detrusor overactivity has proven to be an excellent model to study the effects of drugs on detrusor overactivity. Using this model, we evaluated the responses to intravesical ketoprofen.

Effect of castration on male rabbit lower urinary tract tissue enzymes.

Objectives: The influence of testosterone on the prostate and corpus cavernosum have been studied extensively. However, the influence of testosterone on the lower urinary tract (bladder and urethra) have not been investigated to any great extent. The aim of this study was to determine whether androgen deprivation alters lower urinary tract metabolism.

The effects of cyclical oestrogen on bladder and urethral structure and function.

Objective: To determine the effects of cycling oestrogen in rabbits, as oestrogen is essential for physiological maintenance and integrity of the female urogenital tract.

Materials And Methods: Changes in circulating oestrogen have marked effects on the bladder of experimental animals, with ovariectomy (Ovx) inducing smooth muscle (SM) and mucosal atrophy, increasing collagen synthesis and deposition, decreasing contractile function, mucosal and SM blood flow; oestrogen reverses these effects and increases bladder mass and SM density, primarily by stimulating angiogenesis and increasing blood flow. Twenty adult female New Zealand White rabbits were divided into five equal groups; group 1 served as the control group, and groups 2-5 had a bilateral Ovx.

Effect of bilateral in vivo ischemia/reperfusion on the activities of superoxide dismutase and catalase: response to a standardized grape suspension.

Purpose: Ischemia/reperfusion (I/R) is a major etiological factor in the bladder dysfunctions observed in men with lower tract obstruction, women with postmenopausal incontinence and with aging. A standardized grape suspension protects the rabbit urinary bladder from both the contractile dysfunctions and the morphologic changes mediated by I/R. Using a model of in vivo bilateral ischemia/reperfusion, the current study investigated the effect of this grape suspension on the endogenous antioxidant defense systems.

Role of nitric oxide in urinary bladder function: effect of L-arginine.

Background: Evidence indicates that decreased blood flow to the bladder plays a major role in obstructive bladder dysfunction in the rabbit model of partial bladder outlet obstruction (PBOO), and that nitric oxide (NO) regulation of blood flow may be important in modulating the degree of obstructive bladder dysfunction. The specific aim of our study is to determine the effect of feeding rabbits a diet high in L-arginine on the response to PBOO.

Materials And Methods: Sixteen male NZ White rabbits were separated into 4 groups of 4 each.

Alteration of contractile and regulatory proteins in estrogen-induced hypertrophy of female rabbit bladder.

Objectives: Estrogen is essential to mediate physiologic functions in female bladders. Deficiency of estrogen has been speculated to be an etiologic factor for bladder dysfunction in postmenopausal women. Our previous studies have demonstrated that estrogen supplementation in female rabbits induces a "functional hypertrophy" of the urinary bladder smooth muscle.

Estrogen induces angiogenesis of the female rabbit bladder.

Postmenopausal bladder dysfunction has been speculated to involve decreased circulating estrogen levels. It is our hypothesis that estrogen induces bladder dysfunctions by modulating blood flow to the bladder, i.e.

Effects of dextromethorphan on in vitro contractile responses of mouse and rat urinary bladders.

Purpose: Dextromethorphan (DXM) is a cough-suppressing ingredient in a variety of over-the-counter cough and cold medications. Dextromethorphan elevates the threshold for coughing primarily through a central mechanism. At doses recommended for treating coughs the drug is safe and effective.

Estrogen induced functional hypertrophy and increased force generation of the female rabbit bladder.

Aims: Estrogen is essential for physiological maintenance of the female urogenital tract. It is believed that alterations in female sex hormones play a major role in the etiology and response to urinary tract dysfunctions. In animal studies, ovariectomy (Ovx) results in smooth muscle (SM) weakness and atrophy whereas estrogen supplementation reverses these effects.

The immediate effect of castration on female rabbit bladder blood flow and tissue oxygenation.

Background: The female urinary bladder is a target organ for estrogen. Reductions in circulating estrogen have been associated with urothelial and vaginal atrophy and bladder disorders including incontinence and increased incidence of bladder infections. We determined the effect of short-term ovariectomy on sex hormones, bladder blood flow, and tissue oxygenation in the rabbit model.

Comparative effects of in vitro ischemia on contractile responses of mouse and rat bladders to various forms of stimulation.

Objectives: To compare in an in vitro study the sensitivity of rat and mouse bladders to ischemia and reperfusion. Urinary bladder dysfunction is related to ischemia and reperfusion. Several studies have been conducted in which one animal model was used in the urinary bladder dysfunction experiments, but very few studies have compared the consequences of urinary bladder dysfunction in different species.

Functional changes in bladder tissue from type III collagen-deficient mice.

Objective: Collagen fibers impart tensile strength and transfer tension from bladder smooth muscle cells. We have previously shown that fibrotic bladders are characterized by an increased type III:type I collagen ratio. To determine the effect of decreased type III collagen on bladder function, type III collagen-deficient mice (COL3A1) were studied physiologically.

Effect of maturation and aging on response of rabbit bladder to bilateral in vivo ischemia/reperfusion.

Objectives: To evaluate the impact of maturation and aging on the effect of bilateral in vivo ischemia/reperfusion on bladder function.

Methods: Male rabbits were separated into three groups by age: immature, mature, and aged rabbits; and each group was subdivided into five subgroups. Each rabbit was subjected to 2 hours of bilateral ischemia.

Protective effects of grape suspension on in vivo ischaemia/reperfusion of the rabbit bladder.

Objective: To investigate the potential protective effect of a grape suspension in a rabbit model of in vivo bilateral ischaemia/reperfusion (I/R), which is a causal factor in obstructive bladder dysfunction.

Materials And Methods: Six groups of four New Zealand White rabbits were treated by twice-daily gavage with aqueous grape suspension (groups 1-3) or sugar-water vehicle (groups 4-6) for 3 weeks. Groups 1 and 4 then received bilateral ischaemia for 2 h, and groups 2 and 5 received bilateral ischaemia for 2 h and reperfusion (recovery) for 1 week.

The effect of tamsulosin on the response of the rabbit bladder to partial outlet obstruction.

Aim: To determine if tamsulosin treatment prevents or decreases the incidence and severity of outlet obstruction-induced bladder dysfunction in rabbits.

Materials And Methods: Male New Zealand White rabbits were treated with tamsulosin or vehicle for 4 weeks with treatments initiated 1 week prior to sham or obstruction surgery. Cystometry was done on anesthetized rabbits 21 days after surgery.

Effect of strip length on the contractile dysfunction of bladder smooth muscle after partial outlet obstruction.

Objectives: Partial outlet obstruction mediates decreased contractile responses and increased collagen synthesis; however, it is not known to what extent the increased collagen contributes to contractile dysfunction.

Methods: Sixteen WNZ rabbits were divided into three groups: control, 2-week obstructed, and 2-week sham. Each rabbit was anesthetized, and the bladder was excised and cut into equal width strips of 0.