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We studied micturitional reflexes in 46 unanesthetized adult male cats spinalized at C5-C6 17 to 125 days previously and in eight intact central nervous system chloralosed cats that were used as controls. Urethral pressure profiles, cystosphincterograms with the urethrovesical junction opened and closed, and mechanograms of detrusor and circular and longitudinal urethral muscles were performed. The effect of vesical, urethral, pelvic, or pudendal anesthesia and vesical and urethral mechanical stimulation were studied. Our results suggest that spinalization produces two major types of neurourologic disorders: (1) weakness of detrusor contractor reflexes (vesicovesical and urethrovesical contraction reflexes) and (2) exaggeration of urethral contractor reflexes (urethrourethral contraction reflex, guarding reflex). Secondarily the weakness of detrusor contractions diminishes the efficiency of the urethral reflex relaxation needed for voiding (vesicourethral relaxation reflex). Because of these abnormalities, two main syndromes appear: (1) underactive detrusor function and (2) detrusor sphincter dyssynergia. Isolated peripheral manipulations of the bladder or urethra do not improve micturition: (1) increase in detrusor contraction strength induces detrusor sphincter dyssynergia, and (2) relaxation of the external sphincter facilitates voiding, but urinary retention persists. It is proposed that spinalization produces a central micturitional dysreflexia responsible for the peripheral dysfunction, and treatment must be oriented toward the central dysreflexia rather than the peripheral dysfunction.

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A vesicourethral electromyographic study was carried out on 21 cats of both sexes with extracellular electrodes along with monitoring of contraction and relaxation of various parts of the bladder and urethra. No consistent electromyographic pattern of slow and fast waves was observed in the bladder and urethra either in any empty bladder or during filling and voiding phases. Most of the recorded waves were traced to a defined source of artefact. Twenty-two experiments were done with glass microelectrodes recording intracellularly in bladder strips of various animals bathed in normal and modified Krebs solutions. No spike activity was recorded during periods of contractions, whether spontaneous or electrically stimulated. Both in vivo and in vitro experiments suggest that the mechanism of excitation-contraction coupling of the bladder remains unidentified. The clinical application of bladder electromyography (EMG) has to be interpreted cautiously.

The aim of this study was to verify the validity and reliability of analgesia elicited by acupuncture stimulation in rabbits. Ninety-five experiments were performed using 21 adult animals. The reaction time of the avoidance response elicited by noxious heat stimulation on the snout, and the presence or absence of the start response elicited by pin-prick and clamping of the skin were studied. Bilateral electric acupuncture stimulation in the area of Tsu-san-li and Shang-chu-hsu points in the hind legs was used. The animals were either held in a soft bag, loosely attached by cords, or suspended in a hammock; the eyes were either free of blindfolded. On the basis of operational behavioral measurements, it was found that acupuncture stimulation did not produce analgesia in undisturbed, placid animals. However, during agitated or fighting periods and the immobility reflex-like state, sometimes associated with acupuncture maneuvers, long reaction times were observed. Pin-pricking and clamping stimulation of the skin were not reliable methods of noxious stimulation in the rabbit.