[Morphological and physiological change in the dis-used bladder of hemodialysis patients]

We studied 48 patients who underwent renal transplantation during the period of July, 1983 and May, 1988 and were free of episodes of neurogenic bladder in the past history. The average age was 27.6 +/- 9.5 years old, and mean 24 hour urine output was 249 +/- 396 ml. Cystometry was performed preoperatively in 39 patients. The average bladder capacity decreased to 112 +/- 69 ml (n = 39) and only 29.0% of the patients exhibited normal compliance (> 50 ml/cmH2O) (n = 35). Biopsy of the bladder wall was performed in 22 patients during the operation. The purpose of this study is to ascertain what physiological and pathological change may occur in the disused human bladder with low capacity and low compliance. Response of muscle tissue to carbachol were examined in 7 specimens and that of isoproterenol were examined in 9 patients. The minimum concentration of carbachol at which muscle contraction was exhibited did not differ from that of the control group. The minimum concentration of isoproterenol at which autonomous muscle activity was completely inhibited increased in cases with decreased 24 hour urine output. ED50 value of inhibition by isoproterenol to the muscle contraction during field stimulation exhibited that the inhibitory action of isoproterenol on muscle contraction declined in the cases with decreased 24 hour urine output. Pathological change of the smooth muscle layer were observed in 17 patients. Muscle cell atrophy was recognized in 29.4% of the patients and vacuolar change of smooth muscle cells was seen in 64.7%. Muscle bundle atrophy was observed in 23.5% and fibrosis was seen in 52.9%.