Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033377 (prolapse)
 11,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Coughing or straining evokes reflex bulbocavernosus (BCM) and puborectalis (PRM) muscle contraction, which apparently transforms the vagina into a closed high-pressure cavity. This elevated vaginal pressure counteracts the increased intra-abdominal pressure and the tendency of the uterus to prolapse, and also supports the rectovaginal septum against the high straining-induced intrarectal pressure and possible consequent rectocele (posterior vaginal prolapse) formation. We investigated the hypothesis that a weak BCM and PRM share in the genesis of rectocele by changing the rectovaginal pressure gradient. Twenty-three women with rectocele (mean age 43.2+/-6.6 years) and 12 healthy women volunteers (mean age 41.6+/-6.2 years) were studied. The response of the intrarectal (intra-abdominal) and intravaginal pressure, as well as the EMG activity of the BCM and PRM to straining or coughing, was recorded. In the healthy volunteers the rectal and vaginal pressures showed a significant increase on coughing or straining, with no significant difference between the rectal or vaginal pressures. Also, the BCM and PRM EMG activity exhibited a significant increase. Rectocele patients showed a significantly low resting vaginal pressure. The increase in rectal and vaginal pressure, as well as of the EMG activity of the BCM and PRM on straining or coughing, was significantly lower and the latency of the EMG response was significantly longer than those of the healthy volunteers. A difference in the rectovaginal pressure gradient showing a significant increase in the rectal against the vaginal pressure, particularly on coughing or straining, is suggested to be the basic factor in the genesis of rectocele. This pressure difference appears to be caused by diminished BCM and PRM contractile activity. A disrupted rectovaginal septum is not a prerequisite for rectocele formation, as the septum appears normal in obstructed defecation despite the common occurrence of rectocele. A histopathologic study of the septum in rectocele seems necessary.
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PMID:On the pathogenesis of rectocele: the concept of the rectovaginal pressure gradient. 1461 6

Bulbo/ischiocavernosus muscles (BCM, ICM) were found to contract on straining. We investigated the hypothesis that straining effects cavernosus muscles' contraction through a reflex action. The response of the BCM and ICM electromyographic (EMG) activity to increased intra-abdominal pressure (straining) as recorded by the intravesical pressure was registered in 32 healthy volunteers (age 39.2 +/- 10.3 years, 20 men, 12 women). The latency of the response was recorded. Responses were registered again in 17 subjects after individual anaesthetisation of urinary bladder, BCM, and ICM. BCM and ICM EMG activity increased progressively with increasing straining. It was not evoked after frequent successive straining. Latency decreased gradually with increase of straining intensity. Cavernosus muscles did not respond to straining after bladder and cavernosus muscles had been individually anaesthetised. Straining appears to effect cavernosus muscles' contraction through the 'straining-cavernosus reflex'. Cavernosus muscles' contraction produces compression of the penile and clitoral cavernous tissue. BCM contraction, furthermore, causes narrowing or closure of the vaginal introitus. The vagina is suggested to become a high pressure closed cavity which counteracts the increased intra-abdominal pressure and uterine tendency to prolapse. Meanwhile, the elevated intravaginal pressure presumably supports the rectovaginal septum against the concomitant high intrarectal pressure.
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PMID:A study of the effect of straining on the cavernosus muscles: identification of 'straining-cavernosus reflex' and its clinical significance. 1821 Dec 98