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

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.

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. Groups 3 and 6 were controls (sham-operated). The effects on cystometry, in vitro contractile responses, and morphology were evaluated.

Ischaemia resulted in significant reductions in the contractile responses to all forms of stimulation in vehicle-fed rabbits, whereas there were no reductions in grape-fed rabbits. Contractile responses were significantly reduced in both I/R groups, but significantly more in vehicle-fed than in grape-fed rabbits. Immunohistochemical studies showed less hypoxia in the bladders of grape-fed rabbits than in vehicle-fed rabbits for both ischaemia-only and I/R groups.

Feeding rabbits with grape suspension provided significant protection against the hypoxic effects of bilateral ischaemia and I/R.