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J Winckler

Publications and source records attributed to J Winckler.

11 recordsLinked to original sources
PubMed1977

Light and electron microscopic observations of the autonomic innervation of the mouse gallbladder mucosa. A histochemical, cytochemical, and secretory study.

The autonomic innervation of the mouse gallbladder mucosa was studied using histo- and cytochemical methods. In a light microscopic investigation the distribution of acetylcholinesterase (AChE) activity and formaldehyde-induced fluorescence was studied histochemically. Nerve fibres and small varicosities showed concentrations of AChE activity very close to the epithelium in the subepithelial connective tissue. No adrenergic nerves were observed in the mucosa. When using the electron microscope and employing the potassium permanganate fixation/staining technique only one sort of axonal enlargement was encountered, viz. the cholinergic type. These varicosities contained numerous agranular vesicles (500-600 A in diameter). No varicosities of the adrenergic (dense-cored vesicles) type were observed. Signs of increased secretory activity in the epithelium were observed in the first few minutes after cholinergic stimulation. After repeated in vivo stimulation, there was an almost total depletion of glycoprotein granules, best seen when using the cytochemical PA-CrA-silver technique. The findings suggest that the subepithelial connective tissue and the epithelium of the mouse gallbladder mucosa have a cholinergic innervation.

Acetylcholinesterase↗
PubMed1977

[Histologic-histochemical findings in the salivary glands of guinea pigs after sectioning the chorda tympani].

We investigated Gl. submandibularis and Gl. sublingualis of the guinea-pig 1, 2, 5, 7, 14 und 28 days after section of the Chorda tympani with histological-histochemical methods. The innervation pattern of both glands (Gl. submandibularis: aminergic-cholinergic double innervated; Gl. sublingualis: cholinergic innervated) remains unchanged. In the gland cells the following effects were observed: a) Gl. sublingualis. In the first 3 days apocrine and holocrine secretion phenomena are often seen, suggesting a maximal stimulation of the gland parenchyma. They are accompanied with cellular reactions of the interstitial space. In a second phase a new gland cell population appears that uniformly exhibits intracellular accumulation of secretion products. Involution begins from the 14th day on. Secretory cells are dedifferentiated to intercalated duct cells; autophagic processes help to degradate the accumulated secretion granules. b) Gl. submandibularis. Here the effects are less dramatic. The accumulation of the secretory granules starts as soon as 24 h after section of the Chorda and is maximal between the 5th and 8th p. o. day. Involution of the gland begins from the 14th day on. The accumulated secretory granules show high activities of two histochemically demonstrable enzymes, the cholinesterase and the peroxidase.

Animals↗
PubMed1976

[Biogenic amines in endocrine cells producing polypeptide hormones. The APUD-cells (Pearse) (author's transl)].

APUD-cells (A = Amine, P = Pprecursor, U = Uptake, D = Decarboxylation) are endocrine cells with numerous common characteristics: 1. They produce polypeptide hormones of low molecular weight. 2. They possess specific 1-amino acid decarboxylases to synthesize catecholamines and/or 5-hydroxytryptamine from precursors. 3. A part of the APUD-cell family primarily accumulates biogenic amines within their cytoplasm. 4. All APUD-cells are rich in specific secretory granules that are the morphological substrate for most of their common features.--Enzyme histochemically the APUD-cells represent a rather heterogenous population. The capacity to take up biogenic amines from the blood is confined to a smaller numer of APUD-cells. The concept of the APUD-cells representing a peripheral neurosecretory system (Pearse und Polak, 1971) appears to be premature. It is probable that in several APUD-cells the accumulation of biogenic amines only constitutes a phenomenon without any physiological relevance which, notwithstanding, could explain pathological reactions of APUD-cells.

Animals↗
PubMed1976

[Fixation of enzymes in freeze-dried tissue with gases].

Several gaseous substances were tested for fixation of enzymes in frozen dried cryostat sections. Formaldehyde, glutardialdehyde and phtaldialdehyde vapours are effective in stabilizing lysosomal hydrolyse, so improving their orthotopic localization. Glutardialdehyde and glyoxylic acid vapours are useful fixatives for dehydrogenase histochemistry in frozen dried cryostat sections. Heating of sections alone has no fixating effect on enzymes at all.

Adrenal Glands↗
PubMed1975

Cryosurgical devitalization of bone and its regenreation; An experimental study with animals.

In an experimental study using rabbits, bone is supercooled by means of liquid nitrogen flowing through a silicone chamber. The surrounding soft tissue is protected by a heating element of silicone. The histological findings in the stages of devitalization of osteocytes are described. X-rays and fluorescent labelling were used, searching for the time of total recalcification in supercooled bone.

Animals↗