Biochemical evaluation of obstructive bladder dysfunction in men secondaryto BPH: A preliminary report

Objectives. In the rabbit, two of the major cellular alterations that media te bladder dysfunction secondary to partial outlet obstruction are a decrea sed ability of the sarcoplasmic reticulum (SR) to store and release Ca2+, a nd mitochondrial dysfunction. The objective of the current study was to det ermine whether SR and mitochondrial dysfunctions are associated with sympto matic benign prostatic hyperplasia (BPH) in men. Methods. Bladder biopsies were obtained from men with symptomatic BPH and f rom age-matched men with no urologic dysfunction. Each biopsy was analyzed for the following enzyme activities: malate dehydrogenase and citrate synth ase (mitochondrial markers) and the sarcoplasmic reticular enzyme Ca2+-depe ndent adenosine triphosphatase (ATPase). These values were compared with th e enzyme activities of control rabbit bladder smooth muscle and bladder smo oth muscle obtained from rabbits subjected to 2 weeks of partial outlet obs truction. Results. The enzymatic activities of all three enzymes are significantly lo wer in human bladder smooth muscle than in rabbit bladder smooth muscle. Th e maximal activities of all three enzymes are significantly lower in human bladder samples obtained from men with diagnosed obstructive uropathy than in men of equal age with no urologic dysfunction. Conclusions. These studies demonstrate that similar to the response of the rabbit to partial outlet obstruction, obstructive dysfunction secondary to BPH is characterized by mitochondrial and SR dysfunction. (C) 1999, Elsevie r Science Inc. All rights reserved.