Effect of bladder ischaemia/reperfusion on superoxide dismutase activity and contraction.
OBJECTIVE
To correlate the effect of bilateral in-vivo bladder ischaemia/reperfusion on superoxide dismutase activity (SOD) and then to correlate this with contractile responses to various forms of stimulation.


METHODS
Twenty mature male New Zealand White rabbits were divided into five equal groups: group 1 (controls); group 2, 2 h of in-vivo bilateral bladder ischaemia; and groups 3-5, 2 h of in-vivo ischaemia followed by 1, 7 or 14 days of reperfusion (recovery). At the end of the treatment period, bladder strips were incubated and placed in isolated baths for contractile studies. The contractile responses to field stimulation, carbachol (10 micromol/L), ATP and KCl were determined. The balance of the bladder body was separated into muscle and mucosa sections and analysed for SOD activity.


RESULTS
There were few effects on contraction either directly after ischaemia or after 1 day of reperfusion. However, all contractile responses were significantly reduced at 7 and 14 days after ischaemia. SOD activity of the detrusor muscle was reduced significantly immediately after ischaemia and at 7 and 14 days of reperfusion. SOD activity of the mucosa was significantly greater than that of the muscle, and was significantly reduced by both ischaemia and all times of reperfusion.


CONCLUSIONS
These studies show clearly that both ischaemia and reperfusion result in significantly lower activity of SOD, and in contractile dysfunctions, and that reperfusion results in greater decreases in both SOD activity and contractile responses than ischaemia alone.
Erdem
Erim
E
College of Pharmacy, 106 New Scotland Ave, Albany, NY 12208, USA.
Leggett
Robert
R
Dicks
Brian
B
Kogan
Barry A
BA
Levin
Robert M
RM
D000818:Animals; D007511:Ischemia / Q000201:enzymology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D011817:Rabbits; D015427:Reperfusion Injury / Q000201:enzymology; D013482:Superoxide Dismutase / Q000378:metabolism*; D001743:Urinary Bladder / Q000098:blood supply* / Q000201:enzymology
D013482:Superoxide Dismutase