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1.
Peptides ; 33(2): 230-9, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22289500

ABSTRACT

Elucidating how neuropeptides affect physiology may result in delineating peptidergic mechanisms and identifying antagonists for application in basic and translational science. Human neuropeptide Y (NPY) regulates cardiac activity; frequently invertebrates contain orthologs of vertebrate peptides. We report invertebrate NPY-like neuropeptide F (NPF) arrested the signal frequency of the slow phase of the cardiac cycle (EC50 = 1 pM); however, signal frequency of the fast phase was affected only minimally. Neuropeptide F decreased the duration of the slow phase by ~70% (EC50 = 0.6 pM), but increased the duration of the fast phase by ~57% (EC50 = 10nM). Short NPF-1 (sNPF-1) decreased the signal frequency of the slow phase by ~70% (EC50 = 9 nM); yet, signal frequency of the fast phase was unaffected. Short NPF-1 decreased the duration of the slow phase ~55% (EC50 ~50 nM), but increased the duration of the fast phase ~20% without dose dependency. Neuropeptide F and sNPF-1 increased isoelectric period duration. This novel report demonstrated NPY-like peptides are cardioactive but functionally unique. These data contribute to understanding how invertebrate orthologs affect cardiovascular activity. Dipteran fast and slow phases may be generated from separate pacemakers in the abdominal heart and in the anterior thoracocephalic aorta, respectively. Thus, our research suggests NPF and sNPF-1 act through different mechanisms to regulate cardiac activity. Invertebrate NPY-like peptides act in olfaction and feeding yet mechanisms which are associated with their cardioactive effects remain unknown; our work may provide evidence linking their roles in sensory response and cardiac activity.


Subject(s)
Diptera/physiology , Insect Proteins/physiology , Myocardial Contraction , Myocardium/metabolism , Neuropeptides/physiology , Signal Transduction , Animals , Diptera/metabolism , Male , Stimulation, Chemical
2.
Arch Ital Urol Androl ; 66(4 Suppl): 133-7, 1994 Sep.
Article in Italian | MEDLINE | ID: mdl-7889048

ABSTRACT

The Authors report on their specific experience on the funicular Doppler veocimetry, regarding the varicocele. In particular we enhance the semeiological spects of the C.W. Doppler velocimetry in the sub-clinical varicocele, in the bilateral one and in the characterization of the spermatic and cremasteric refluxes, and of the external pudenda vein. The Authors stress the utility of the definition of the amount of the reflux, so achieving an integration with the existing classification by degrees, that as it is now days expressed, it seems, to regard the elapsed time and the quantity of reflux caused by the Valsalva manoeuvre. In the practical velocimetry those elements have not been proved to have a parallel increment. Lastly, we report on some cases of veno-spermatic refluxes, uniquely observed in the clynostatism, along with a missing orthostatism. Moreover the Authors believe that some of these hemodynamical consideration could be revisited.


Subject(s)
Varicocele/diagnostic imaging , Humans , Male , Ultrasonography , Varicocele/classification , Varicocele/physiopathology
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