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)

The dose-effect relationships of intraventricularly injected bradykinin, Gly-Arg-Met-Lys-bradykinin (GAML-bradykinin), synthetic substance P and angiotensin II on lever-lifting behavior of rabbits in a variable-interval (VI) 72-second schedule of sweetened water presentation were determined. All peptides used caused dose-dependent decreases in overall rates of VI responding during the experimental session in the following order of potency: angiotensin II greater than bradykinin = substance P greater than GAML-bradykinin. The angiotensin II dose-effect curve was less steep than those of the other peptides. The administration of nearly equimolar doses of the bradykinin potentiating peptides, BPP5a and BPP9a, slightly decreased overall VI response rates and caused a 10- to 20-fold potentiation of the rate-decreasing effect of bradykinin on VI responding. Both angiotensin II and bradykinin caused pauses in responding of dose-dependent duration at the beginning of the experimental session that were followed by normal VI responding. The effect of GAML-bradykinin on VI performance was similar to that of bradykinin and angiotensin II but had a delay of onset of 3 to 6 minutes. In contrast, substance P caused actual decreases in response output and pauses of variable duration interspersed between periods of regular VI responding. At the doses used, both bradykinin-potentiating peptides caused uniform decreases in VI responding throughout the experimental session. Gross behavioral changes caused by the peptides were also observed. After the intraventricular injection of bradykinin or GAML-bradykinin, rabbits showed decreased motility, ptosis, miosis and lowered ears; after angiotensin II, animals remained motionless but with wide open eyes, fully raised ears and no miosis. In turn, substance P caused restlessness and increased locomotion. These results together with reported evidence on other powerful central actions of bradykinin, angiotensin and substance P and on the existence of components of their releasing and destroying enzymatic systems in the brain suggest that linear peptides may play a role in the functioning of the central nervous system.
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PMID:Effect of intracerebroventricular bradykinin and related peptides on rabbit operant behavior. 109 6

The clinical implication of the timing of mitral regurgitation (MR) in mitral valve prolapse (MVP) was investigated by comparison of the phonocardiographic patterns of the regurgitant murmur with either prolapsing phase of the mitral valve determined by two-dimensional echocardiography (TDE) or regurgitant flow patterns by pulsed Doppler echocardiography (PDE). A total of 23 patients (pts) with MVP was classified into five subsets on the basis of the phonocardiographic findings: six pts with a pansystolic murmur, seven with a late systolic murmur, two with an early systolic murmur, three with only a click(s) and five with a angiotensin II-induced regurgitant murmur (provocative MR). A comparative study between the regurgitant murmur and regurgitant flow patterns was also made in 10 pts with MR due to other etiology (four pts of rheumatic MR, three of ruptured chordae tendineae and three of papillary muscle dysfunction). MR was detected at or just above the mitral orifice using a combined system of the PDE and TDE from a transcutaneous approach. The results obtained were as follows: Phase of MR detected by PDE coincided well in timing with a regurgitant murmur recorded on the phonocardiogram (PCG) except one patient. In four of five pts with provocative MR, abnormal Doppler signals indicating MR were detected even at rest and these coincided temporally with a newly developed regurgitant murmur by provocation. Phase of MR detected by PDE was not synchronous with prolapse of the mitral leaflets examined by TDE in five out of 23 pts, suggesting that MR does not necessarily occur in accordance with mitral prolapse. Regurgitant flow patterns examined by PDE in 30 pts including 10 pts of MR due to other etiology were either a widely dispersed dot pattern or a narrow banded reverse flow pattern. Pts with a loud systolic regurgitant murmur (Levine 3/6 or greater) tended to show a widely dispersed dot pattern, and pts with a soft systolic regurgitant murmur (less than Levine 2/6) showed a narrow banded reverse flow pattern. In conclusion, PDE seems to be more sensitive than PCG for the detection of MR in MVP, and PDE may serve to the qualitative as well as quantitative evaluation of MR in MVP.
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PMID:[Phase analysis of mitral regurgitation in mitral valve prolapse: comparison of pulsed Doppler echocardiography with phonocardiography]. 667 87