EXPERIMENTAL STUDIES ON THE NEUROGENIC BLADDER

XIV. BIOPHYSICAL ANALYSIS OF BASAL RHYTHM OF THE BLADDER

Abstract

“Neurogenic Bladder” includes all dysfunctions and diseases of the urinary bladder due to organic disorders arising in the central, peripheral or intrinsic nervous system of the bladder.
Up to the present, the cystometrogram was thought to reveal directly such causal nervous disorders of this disease as well as the activity of the residual innervation. However, recent studies in our department offered a new concept for the clinical evaluation of the cystometrogram as it represent the physiological and histological properties of the vesical wall itself involving the activity of the intramural ganglions. Therefore, the author had tried to examine the physiological nature of the normal dog bladder as well as that of the experimental neurogenic bladder with the observation on “Basal Rhythm” (B. R.), in order to clarify the difference between these two conditions.
B. R. is a small but rather regular contraction of the vesical wall which is found during isometric cystometryo The standard dimensions of it in a normal dog are as follows: amplitude: 0.5-6.0cmH₂O, duration: 10-20sec., frequency: 1 time/5-6min. to continuous. It becomes gradually prominent as the bladder is filling, and at last it is fused to produce micturition contraction.
While, the mode of B. R. is altered showing a regular pattern after the systematic section of the nerve innervating the urinary bladder, as follows:
(1) Brain: resection of the frontal cerebral cortex, disappeared; total resection of the cerebrum, reappeared; rostal supracollicular decerebration, activated; caudal infracollicular decerebration, disappeared.
(2) The spinal cord: section of the 7th cervical and/or the 4th thoracic cord, almost no effect; section of the 6th lumbar cord, slightly reduced.
(3) Sacral nerve: section of the ventral root, reduced; section of the dorsal root, reduced; section of the ventral-and-dorsal root, reduced; resection of the spinal ganglion, activated
(4) Peripheral nerve: section of the hypogastric nerve, markedly activated; section of the pelvic nerve, activated; section of the pudendal nerve, no effect.
(5) Miscellaneous: extirpated bladder, activated and regular; ice-cooled bladder (4 hours and 24 hours), disappeared; pharmacological stimulation of the bladder, specific responses corresponding to the kind of the drug.
Next, B. R. of the experimental neurogenic bladder in the dog was examined one month after selective sections of the ventral, the dorsal, the ventral-and-dorsal root of the sacral nerve, resection of the spinal ganglion of the same nerve, and section of the hypogastric or the pelvic nerve, respectively. Neither characteristic difference of the mode of B. R. between these neurogenic bladders nor that in the normal bladder could be found. However, it was clearly found that there were characteristic differences between the alteration pattern of the mode of B. R. after systematic section of the residual innervation between normal and these abnormal bladders.
The marked findings in this differing from that of normals were as follows:
(1) Section of the 7th cervical cord: reduced or disappeared in all cases except the ventral rootresected bladder.
(2) Section of the 6th lumbar cord: specific reactions corresponding to the kind of prior nerve section.
(3) Section of the hypogastric nerve: reduced or disappeared in all cases except the spinal ganglionresected bladder. This was the most significant result of the neurogenic bladders compared to that of the normals.
(4) Section of the pelvic nerve: no effect in ventral root-resected or dorsal root-resected bladders; reduced in the spinal ganglion-resected bladder.
With the results obtained above, it was clarified that:
(1) The mode of B. R. in the normal bladder was affected by the amount of intravesical content as well as the activity of the nervous innervation from the central to the peripheral.
(2) The mode of B. R. in the