The effect of alpha-blocker treatment on bladder hypoxia inducible factor-1 alpha regulation during lower urinary tract obstruction

Abstract

AIMS: To determine whether α1-blocker treatment, in chronic bladder outlet obstruction (BOO), influences bladder tissue ischemia. MATERIALS AND METHODS: This prospective study included 60 patients with BOO, of which 40 were under α1-blocker medication and 20 without treatment. Patients underwent transurethral resection of the prostate (TURP) or suprapubic prostatectomy (SPP). Ten patients with non-muscle invasive bladder cancer underwent transurethral resection of the bladder tumor and served as the control group. Tissue specimens were immunohistochemically stained for hypoxia inducible factor-1α (HIF-1α). RESULTS: Bladder tissue from obstructed subjects showed high immunoreactivity to HIF-1α. The specimens from the control group, showed no or weak, mainly cytoplasmic immunoreactivity to HIF-1α. Patients under α -blocker treatment did not differ in the number of HIF-1α positive cells compared to subjects with no treatment (median number 86.8 [20-150] and 88.6 [0-175], respectively) (p > 0.05). The lowest bladder pressure at which HIF-1α was up regulated, was detected at detrusor pressure Qmax (PdetQmax) = 60 cm H2O. CONCLUSIONS: Treatment with α-blockers in obstructed patients considered as non-responders, does not result in HIF-1α down regulation, thus bladder continues to be under chronic stress.

Keywords

• bladder
• bladder outlet obstruction
• hypoxia inducible factor-1
• ischemia
• alpha-blockers