Substance P in Nerve Tissue in the Gut

Previous research has revealed that passive (involuntary inhalation) tobacco smoking during gestation can have adverse effects upon the developing fetus. These prior investigations did not concentrate on changes in fetal morphology. This study was undertaken to delineate fetal neural abnormalities at the ultrastructural level in mice pups exposed in utero to passive maternal smoking.Pregnant study animals, housed in a special chamber, were subjected to cigarette smoke daily from conception until delivery. Blood tests for determination of carbon monoxide levels were run at 15-18 days gestation. Sciatic nerve tissue from experimental and control animals were obtained following spontaneous delivery and fixed in 2.5% gluteraldehyde in 0.1M cacodylate buffer pH 7.3. The samples were post-fixed in osmium ferrocyanide (1:1 mixture of 1.5% aqueous OSO4 and 2.5% K4 Fe(CN)6). Following dehydration, the tissues were infiltrated with and embedded in Spurr. Sections were stained with uranyl acetate and lead citrate.

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Mast cell-nerve fiber interaction: Ultrastructural studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159680 ◽

1990 ◽

Vol 48 (3) ◽

pp. 428-429

Author(s):

E.Y. Chi ◽

M.L. Su ◽

Y.T. Tien ◽

W.R. Henderson

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Substance P ◽

Nerve Fiber ◽

Sensory Nerves ◽

Ultrastructural Studies ◽

Morphological Studies ◽

Granulocyte Infiltration ◽

Intracutaneous Injection ◽

Recent Attention

Recent attention has been directed to the interaction of the nerve and immune systems. The neuropeptide substance P, a tachykinnin which is a neurotransmitter in the central and peripheral nervous systems produces tissue swelling, augemntation of intersitial fibrin deposition and leukocyte infiltration after intracutaneous injection. There is a direct correlation reported between the extent of mast cell degranulation at the sites of injection and the tissue swelling or granulocyte infiltration. It has previously been demonstrated that antidromic electrical stimulation of sensory nerves induces degranulation of cutaneous mast cells, cutaneous vasodilation and augmented vascular permeability. Morphological studies have documented a close anatiomical association between mast cells and nonmyelinated nerves, that contain substance P and other neuropeptides. However, the presence of mast cells within nerve fasicles has not been previously examined ultrastructurally. In this study, we examined ultrastructurally the distribution of mast cells in the nerve fiber bundles located in the muscular connective tissue of rat tongues (n=20).

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Immunocytochemical methodology for the localization of neuronal antigens at the ultrastructural level

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161941 ◽

1990 ◽

Vol 48 (3) ◽

pp. 876-877

Author(s):

Jorge Pecci Saavedra ◽

Mark Connaughton ◽

Juan José López ◽

Alicia Brusco

Keyword(s):

Spinal Cord ◽

Substantia Nigra ◽

Polyclonal Antibodies ◽

Ultrastructural Level ◽

Point Of View ◽

Nerve Tissue ◽

Tissue Fixation ◽

Optimal Conditions ◽

Interpeduncular Nucleus ◽

Technical Point

The use of antibodies as labels for the localization of specific molecules in the nervous systan has been extensively applied in recent years. Both monoand polyclonal antibodies or antisera have been employed. The knowledge of the organization of neuronal connectivities, gliovascular relationships, glioneuronal relationships and other features of nerve tissue has greatly increased.A number of areas of the nervous systan have been analyzed in our laboratory, including the nuclei of the raphe system, the reticular formation, interpeduncular nucleus, substantia nigra, caudate nucleus, putamen, pallidum, spinal cord, pineal gland and others.From a technical point of view, a number of variables needed to be taken into account in order to obtain reliable and reproducible results. The design of the optimal conditions of tissue fixation, embedding, sectioning, dilution of antibodies, and adaptation of Sternberger PAP technique were sane of the parameters taken into account to optimize the results. It is critical that each step of the technique be defined for each particular case.

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