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L Zilletti

Publications and source records attributed to L Zilletti.

71 records · Page 4Linked to original sources
PubMed1970

The Schultz-Dale response of the longitudinal muscle strip preparation of guinea-pig ileum.

1. The mast-cell distribution in the various layers of the ileum has been described.2. Histamine-content, anaphylactic histamine-release and the anaphylactic dose-response curve of the full-thickness ileum and of the longitudinal muscle strip have been measured and compared.3. Tetrodotoxin 10(-7) g/ml had no obvious effect on the anaphylactic dose-response curve of either preparation. This suggests that the plexus is not of any great importance in the Schultz-Dale reaction.4. Exposure of the longitudinal muscle strip to octylamine 10(-3) g/ml for 1 min reduced the mast cell content by 95-100%. After this treatment the dose-response curve to antigen was eliminated, although the muscle still responded to small doses of histamine and to anaphylactic mediators. Pretreatment of antibody with octylamine did not impair passive sensitization and subsequent response to antigenic challenge. This suggests that the classical Schultz-Dale reaction in the strip is mediated mainly by mast cells, and possibly other cells, and is probably not due to a direct effect of the antigen-antibody reaction on the smooth muscle.5. The typical three-phase anaphylactic response (quick contraction, quick relaxation, slow contraction) of full-thickness ileum is discussed and compared with the predominantly two-phase response of the longitudinal muscle strip. No evidence was found for the release of a relaxation-factor. It is suggested that the initial fast phase may be due to mediators released from mast cells among the longitudinal muscle fibres, and the sustained contraction to a second wave of mediators reaching the longitudinal muscle from deeper layers of the ileum.

Amines↗
PubMed1966

The influences of andrenotropic drugs and noradrenaline on the histamine release in cardiac anaphylaxis in vitro.

1. The regional distribution (auricles, ventricles and septum) of histamine and its release during anaphylaxis were studied in isolated perfused guinea-pig hearts.2. The highest value of histamine content was found in the right auricle, the lowest in the left ventricle and septum, both in normal hearts, and in the hearts subjected to anaphylaxis.3. The fraction of the total histamine released in the course of 24 min by antigen was 50%. The fraction released from the different regions of the heart was similar. No evidence was found for release of 5-hydroxytryptamine.4. A relation was found between the distribution of mast cells and the tissue concentration of histamine. The highest number of mast cells per unit area was found in the right auricle; the lowest in the left ventricle.5. The histamine release by antigen was reduced by previous treatment with (+)-tubocurarine; the histamine release by (+)-tubocurarine was depressed by previous challenge of the heart with antigen.6. Reserpine reduces histamine release. Perfusion of reserpine-treated hearts with noradrenaline partially restored histamine release.7. beta-Adrenergic blocking agents (dichloroisoproterenol and pronethalol) reduced histamine release.8. The drugs tested did not modify the tissue concentration of histamine.9. The possibility of a modulating activity of catecholamines on histamine release in cardiac anaphylaxis is discussed.

Anaphylaxis↗
PubMedDate not supplied

Neurological disorders of the myenteric plexus: a review.

The myenteric plexus is the neuronal complex that regulates the motility of the gut; a brief review of its pathology is presented in this paper as well as a tentative etiopathogenetic classification. Disorders of gut innervation include congenital (e.g. Hirschsprung's disease) or acquired diseases; the latter can be idiopathic or related to a more general pathological involvement of the whole organism as in the case of bacterial toxins, diabetes mellitus, Riley-Day disease and primary orthostatic hypotension. In view of the fundamental similarity of the myenteric plexus to the central nervous system, the study of this organ can be useful both for diagnosis of degenerative diseases of the central nervous system (i.e. via rectal biopsy) and for gaining a better etiopathogenetic insight into peripheral and central nervous system disease.

Alcoholism↗