THE SPECIFICITY OF THE ARGYROPHIL REACTION IN THE ISLETS OF LANGERHANS IN MAN

ABSTRACT By studying the Islets of Langerhans in man in thin Bouin fixed paraffin sections, first after impregnation with silver, and subsequently after removal of the silver, stained with Gomori's chrome-haematoxylin or aldehyde-fuchsin, it was possible to assess the specificity of the argyrophil reaction. Reports in the literature that some of the B cells were also silver impregnated could not be confirmed. On the other hand, the argyrophil reaction was not characteristic for all the A cells, since a minority of them were not blackened. In agreement with these observations, the considerably higher frequency of silver cells over A cells, previously reported in connection with comparative differential cell counts on the same human pancreas material, was shown to be only apparent.

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A FLUORESCENT REACTION FOR MONOAMINES IN THE INSULIN PRODUCING CELLS OF THE GUINEA-PIG

Acta Endocrinologica ◽

10.1530/acta.0.0450133 ◽

1964 ◽

Vol 45 (1) ◽

pp. 133-138 ◽

Cited By ~ 46

Author(s):

Bengt Falck ◽

Bo Hellman

Keyword(s):

B Cells ◽

Islets Of Langerhans ◽

Silver Impregnation ◽

Fluorescent Light ◽

Storage Site ◽

Insulin Producing Cells ◽

Freeze Dried ◽

Aldehyde Fuchsin ◽

Fluorescent Products ◽

Fluorescent Cells

ABSTRACT Certain catecholamines and tryptamines condense in freeze-dried tissues with formaldehyde to form intensely fluorescent products. A distinct fluorescence has recently been demonstrated in the islets of Langerhans from several species with this sensitive and specific technique. The fluorescent reaction of the islets has been studied in more detail in the guineapig. Using a combination of fluorescence microscopy with subsequent silver impregnation and granule staining on the same section it was found that the fluorescent cells were identical with the B cells. The B cells exhibited no, or only weak, fluorescence after administration of reserpine. The colour of the emitted fluorescent light suggests that the B cells contain a tryptamine rather than a catecholamine. Since the fluorescent material was distributed in fine cytoplasmic granules the amine may be associated with the aldehyde-fuchsin positive granules which are regarded as the storage site for insulin or some insulin precursor. No support was found for the previous concept of an adrenergic parenchymatous innervation of the islets of Langerhans.

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THE OCCURRENCE OF ARGYROPHIL CELLS IN THE ISLETS OF LANGERHANS OF AMERICAN OBESE-HYPERGLYCAEMIC MICE

Acta Endocrinologica ◽

10.1530/acta.0.0360596 ◽

1961 ◽

Vol 36 (4) ◽

pp. 596-602 ◽

Cited By ~ 85

Author(s):

Bo Hellman

Keyword(s):

Islets Of Langerhans ◽

Islet Cells ◽

Relative Proportion ◽

Paraffin Sections ◽

Argyrophil Cells ◽

American Variety ◽

A Cells ◽

Excessive Secretion ◽

Obese Hyperglycaemic Syndrome

ABSTRACT Distinct argyrophil islet cells were found in thin paraffin sections of pancreas both from normal mice and from those with the American variety of the obese-hyperglycaemic syndrome. In the obese animals the relative proportion of argyrophil cells was only about half as great as in their thin litter mates. In both groups the argyrophil cells were mainly localized to the periphery in the larger islets. The results are discussed in the light of the hypothesis put forward by Mayer et al. (1953), that hyperglycaemia in the obese strain results from excessive secretion of glucagon from the A cells.

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NUCLEAR DIFFERENCES BETWEEN THE ARGYROPHIL (= A1) AND NON-ARGYROPHIL (= A2) PANCREATIC A CELLS IN THE DUCK

Acta Endocrinologica ◽

10.1530/acta.0.0360603 ◽

1961 ◽

Vol 36 (4) ◽

pp. 603-608 ◽

Cited By ~ 6

Author(s):

Bo Hellman

Keyword(s):

Islets Of Langerhans ◽

Functional Activity ◽

Biological Significance ◽

Nuclear Size ◽

Cell Group ◽

A Cells ◽

A Cell ◽

Homogeneous Cell ◽

Argyrophil Reaction

ABSTRACT Previous investigations have shown that the A cells in the islets of Langerhans do not constitute a homogeneous cell group, but can be divided into two distinct fractions, on the basis of the presence (= A1 cells) and the absence (= A2 cells) of an argyrophil reaction. In order to asses the biological significance of this finding, it is important in the first instance to study, whether the A cells show any other mutual differences. In a comparison of the A1 and A2 cells within the dark A cell islets from ducks, significant differences were obtained with regard to nuclear size and eccentricity. The larger nuclear size in the A1 cells is possibly an expression of the higher functional activity in these cells. The findings support the concept of two different forms of the A cells.

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SOME ASPECTS OF SILVER IMPREGNATION OF THE ISLETS OF LANGERHANS IN THE RAT

Acta Endocrinologica ◽

10.1530/acta.0.xxxv0518 ◽

1960 ◽

Vol XXXV (IV) ◽

pp. 518-532 ◽

Cited By ~ 183

Author(s):

Claes Hellerström ◽

Bo Hellman

Keyword(s):

Islet Cells ◽

Paraffin Sections ◽

Treatment Results ◽

A Cells ◽

Separate Fraction ◽

Optimal Period ◽

Impregnation Time ◽

Short Time ◽

Argyrophil Reaction ◽

Essential Prerequisite

ABSTRACT By using a modification of Davenport's alcoholic silver nitrate method for impregnating nerves, it was possible to obtain a distinct argyrophil reaction on thin paraffin sections from rat pancreas which had been fixed either in formalin or Bouin's solution. Since this was followed by a removal of silver with subsequent granule staining according to Gomori, it became clear that the distinctly blackened cells comprised only some of the A cells. Some post-mortem change seemed to be an essential prerequisite of the argyrophil reaction, since this almost completely failed to appear after fixation in an ice-cold Bouin's solution. The reducing material was considerably resistent to acids; strongly blackened islet cells could be observed even after refixation in hydrochloric acid at a pH of 0.5. Although a preoxidation, e. g. with an acid solution of potassium permanganate, is essential for the differentiation of the islet cells with the modern granule stains, such treatment results in the argyrophil reaction becoming weaker or not appearing at all. Actual blackening, except in the case of those A cells, which could be distinguished as silver cells even after a short time, could not be produced by lengthening the impregnation time, but instead, the argyrophil reaction tended to decrease after a certain optimal period. The observation that among those cells, which by granule staining were classified as A cells, a separate fraction with distinctly blackened cytoplasm could be distinguished, led to the suggestion that the blackened cells should be called A1 cells and the remaining ones, A2 cells.

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Effects of Neuroendocrine Centers on Germ and Germline Cells in Dendrobaena atheca Cernosvitov (Annelida: Lumbricidae)

Journal of Morphological Sciences ◽

10.1055/s-0039-1693720 ◽

2019 ◽

Vol 36 (04) ◽

pp. 237-246

Author(s):

Najem Shlemoon Gorgees ◽

Ziyad Tahseen Kiret

Keyword(s):

Experimental Study ◽

B Cells ◽

Blood Capillary ◽

C Cells ◽

Serial Sections ◽

Blood Capillaries ◽

A Cells ◽

Aldehyde Fuchsin ◽

Staining Techniques ◽

Histological Staining

AbstractThe aim of the present comprehensive experimental study was to reveal the effects of the removal and the regeneration of the main neuroendocrine centers in the oogonia, oocytes and trophocytes in Dendrobaena atheca. Various types of serial sections of ovaries and cephalic regions were obtained. Four histological staining techniques were employed. In controlled preparations, the neurosecretory activities of A-cells and C-cells showed correlation with cellular activities of oogonia, oocytes and trophocytes. In experimental preparations, removal of A-cells caused abnormalities in oocytes and trophocytes. The regeneration of A-cells restored vitellogenesis and repaired abnormalities. In both preparations, C-cells remained aldehyde-fuchsin (AF)-positive. B-cells and U-cells remained AF-negative. The oogonia showed continuous mitotic divisions. Regenerated A-cells appeared in week 3, increased in number, but could not stop the abnormalities, as hormones were not transported due to the lack or scarcity of blood capillaries. Therefore, abnormalities increased extremely. Then, they stopped, decreased, and were repaired due to hormonal transport via fully reconstructed blood capillary plexuses. The main conclusions are: (1) oocytes and trophocytes are controlled by A-cells, since they exhibited prominent changes during the removal and regeneration of A-cells; (2) oogonia are controlled by C-cells, as they showed correlation of activities with C-cells and were not affected by the removal and regeneration of A-cells; (3) B-cells and U-cells remained inactive; hence, they have no role in oogonia divisions and vitellogenesis; and (4) delayed hormonal effects of regenerated A-cells were due to the lack or scarcity of blood capillaries. Therefore, fully reconstructed blood capillary beds in the A-cells area are indispensable for hormonal diffusion, transport and effectivity.

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IMMUNOLOGICAL REACTIVITY OF INSULIN IN HUMAN SERUM

Acta Endocrinologica ◽

10.1530/acta.0.0530673 ◽

1966 ◽

Vol 53 (4) ◽

pp. 673-680 ◽

Cited By ~ 5

Author(s):

Torsten Deckert ◽

Kai R. Jorgensen

Keyword(s):

Normal Subjects ◽

The Other ◽

Human Pancreas ◽

Porcine Pancreas ◽

Crystalline Insulin ◽

Endogenous Insulin ◽

Significant Difference ◽

Human Sera ◽

Normal Human ◽

The One

ABSTRACT The purpose of this study was to investigate whether a difference could be demonstrated between crystalline insulin extracted from normal human pancreas, and crystalline insulin extracted from bovine and porcine pancreas. Using Hales & Randle's (1963) immunoassay no immunological differences could be demonstrated between human and pig insulin. On the other hand, a significant difference was found, between pig and ox insulin. An attempt was also made to determine whether an immunological difference could be demonstrated between crystalline pig insulin and crystalline human insulin from non diabetic subjects on the one hand and endogenous, circulating insulin from normal subjects, obese subjects and diabetic subjects on the other. No such difference was found. From these experiments it is concluded that endogenous insulin in normal, obese and diabetic human sera is immunologically identical with human, crystalline insulin from non diabetic subjects and crystalline pig insulin.

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Overexpression of Transcripts Coding for Renin-b but Not for Renin-a Reduce Oxidative Stress and Increase Cardiomyoblast Survival under Starvation Conditions

Cells ◽

10.3390/cells10051204 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1204

Author(s):

Heike Wanka ◽

Philipp Lutze ◽

Alexander Albers ◽

Janine Golchert ◽

Doreen Staar ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

B Cells ◽

Apoptotic Cell ◽

Renin Angiotensin System ◽

Glucose Deprivation ◽

Protective Effects ◽

Glucose Depletion ◽

A Cells ◽

Apoptosis And Necrosis

A stimulated renin-angiotensin system is known to promote oxidative stress, apoptosis, necrosis and fibrosis. Renin transcripts (renin-b; renin-c) encoding a cytosolic renin isoform have been discovered that may in contrast to the commonly known secretory renin (renin-a) exert protective effects Here, we analyzed the effect of renin-a and renin-b overexpression in H9c2 cardiomyoblasts on apoptosis and necrosis as well as on potential mechanisms involved in cell death processes. To mimic ischemic conditions, cells were exposed to glucose starvation, anoxia or combined oxygen–glucose deprivation (OGD) for 24 h. Under OGD, control cells exhibited markedly increased necrotic and apoptotic cell death accompanied by enhanced ROS accumulation, loss of mitochondrial membrane potential and decreased ATP levels. The effects of OGD on necrosis were exaggerated in renin-a cells, but markedly diminished in renin-b cells. However, with respect to apoptosis, the effects of OGD were almost completely abolished in renin-b cells but interestingly also moderately diminished in renin-a cells. Under glucose depletion we found opposing responses between renin-a and renin-b cells; while the rate of necrosis and apoptosis was aggravated in renin-a cells, it was attenuated in renin-b cells. Based on our results, strategies targeting the regulation of cytosolic renin-b as well as the identification of pathways involved in the protective effects of renin-b may be helpful to improve the treatment of ischemia-relevant diseases.

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The immunological characterization of several human ribonucleases by using primary binding tests

Biochemical Journal ◽

10.1042/bj1630419 ◽

1977 ◽

Vol 163 (3) ◽

pp. 419-426 ◽

Cited By ~ 18

Author(s):

E A Neuwelt ◽

M Schmukler ◽

M S Niziak ◽

P B Jewett ◽

C C Levy

Keyword(s):

Human Plasma ◽

Cross Reaction ◽

The Other ◽

Human Pancreas ◽

Human Tissues ◽

Antigenic Difference ◽

Immunological Characterization ◽

Similarities And Differences

RNAases (ribonucleases), purified from four human tissues, as well as bovine pancreatic RNAase (RNAase A), were studied by immunodiffusion methods and by two different primary binding tests. The enzymes fell into two groups immunologically, those purified from plasma and pancreas in one and those from spleen and liver in the other. No antigenic cross-reaction between the two groups was detected by any of the immunoassays used. There was a slight antigenic cross-reaction between the human and bovine pancreatic RNAases. The liver and spleen RNAases were immunologically identical by all criteria used, whereas a small but consistent antigenic difference between the human plasma and human pancreas enzymes was detected. The significance of this difference between the human plasma and pancreas RNAases is discussed in relation to similarities and differences in their properties.

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CYTOCHEMICAL LOCALIZATION OF ADENYL CYCLASE ACTIVITY IN RAT ISLETS OF LANGERHANS

Journal of Histochemistry & Cytochemistry ◽

10.1177/20.11.873 ◽

1972 ◽

Vol 20 (11) ◽

pp. 873-879 ◽

Cited By ~ 119

Author(s):

S. L. HOWELL ◽

MARGARET WHITFIELD

Keyword(s):

B Cells ◽

Islets Of Langerhans ◽

Adenosine Triphosphate ◽

Adenyl Cyclase ◽

Cyclase Activity ◽

Cytochemical Localization ◽

Adenyl Cyclase Activity ◽

Rat Islets ◽

Rat Islets Of Langerhans ◽

A And B Cells

A cytochemical method has been used to investigate the localization of adenyl cyclase activity in A and B cells of isolated rat islets of Langerhans. Adenosine triphosphate was initially utilized as substrate, the pyrophosphate liberated being precipitated by lead ions at its site of production. The specificity of the method was increased by the use of adenylyl-imidodiphosphate as an alternative substrate; this adenosine triphosphate analogue was not hydrolyzed by adenosine triphosphatase but provided an effective substrate for adenyl cyclase. Adenyl cyclase activity, which was found to retain its glucagon and fluoride sensitivity in glutaraldehyde-fixed tissue, was found exclusively and almost uniformly in the plasma membranes of A and B cells. Storage granule membrane, incorporated into the plasma membrane during secretion of the granule content by exocytosis, appeared to be devoid of adenyl cyclase activity.

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