Biochemical and morphological effects of bladder pumping on the urinary bladder in rats.
OBJECTIVE
To study the influence of bladder pumping on the urinary bladder in 44 female rats.


METHODS
Under halothane anesthesia, a urethral catheter was inserted into the bladder of 27 rats, and air (0.4-0.8 mL) was pumped in and out of the bladder at 0.5 cycles/second for a period of 5 minutes. Twenty-four hours after pumping, the bladder was harvested for measurement of the tissue levels of myosin, actin, and nerve growth factor, as well as for electron microscopy. In nine of the 27 rats, cystometry was performed without anesthesia before and 1, 7, 30, and 90 days after bladder pumping. The remaining 17 rats that did not undergo pumping were anesthetized and their bladders were harvested as a control.


RESULTS
Bladder pumping increased the bladder capacity and decreased the maximum bladder contraction pressure, but did not increase the residual volume. Bladder pumping also increased the tissue level of nerve growth factor and decreased the levels of myosin and actin. Electron microscopy showed degeneration of bladder smooth muscle cells and nerve fibers after bladder pumping, as well as derangement and disruption of collagen fiber bundles in the bladder wall. These functional and morphological effects of pumping disappeared within 90 days.


CONCLUSIONS
Bladder pumping therapy appears to have various effects on the bladder wall collagen fiber bundles, smooth muscle cells, and nerves.
Sugaya
Kimio
K
Department of Urology, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan. sugaya@med.u-ryukyu.a.jp
Nishijima
Saori
S
Hatano
Tadashi
T
Ogawa
Yoshihide
Y
Kudo
Takamasa
T
Nishizawa
Osamu
O
D000199:Actins / Q000378:metabolism; D000818:Animals; D003094:Collagen / Q000648:ultrastructure; D005260:Female; D007327:Insufflation; D008854:Microscopy, Electron; D009130:Muscle, Smooth / Q000648:ultrastructure; D009218:Myosins / Q000378:metabolism; D020932:Nerve Growth Factor / Q000378:metabolism; D009994:Osmolar Concentration; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D001743:Urinary Bladder / Q000502:physiology* / Q000648:ultrastructure*; D014563:Urodynamics
D000199:Actins; D003094:Collagen; D020932:Nerve Growth Factor; D009218:Myosins