scholarly journals Dual Mode of Action of Acetylcholine on Cytosolic Calcium Oscillations in Pancreatic Beta and Acinar Cells In Situ

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1580
Author(s):  
Nastja Sluga ◽  
Sandra Postić ◽  
Srdjan Sarikas ◽  
Ya-Chi Huang ◽  
Andraž Stožer ◽  
...  
Keyword(s):  
Beta Cells ◽  
Acinar Cells ◽  
Cell Types ◽  
Cytosolic Calcium ◽  
Calcium Oscillations ◽  
The Body ◽  
Cholinergic Innervation ◽  
Oscillatory Activity ◽  
Tissue Slices

Cholinergic innervation in the pancreas controls both the release of digestive enzymes to support the intestinal digestion and absorption, as well as insulin release to promote nutrient use in the cells of the body. The effects of muscarinic receptor stimulation are described in detail for endocrine beta cells and exocrine acinar cells separately. Here we describe morphological and functional criteria to separate these two cell types in situ in tissue slices and simultaneously measure their response to ACh stimulation on cytosolic Ca2+ oscillations [Ca2+]c in stimulatory glucose conditions. Our results show that both cell types respond to glucose directly in the concentration range compatible with the glucose transporters they express. The physiological ACh concentration increases the frequency of glucose stimulated [Ca2+]c oscillations in both cell types and synchronizes [Ca2+]c oscillations in acinar cells. The supraphysiological ACh concentration further increases the oscillation frequency on the level of individual beta cells, inhibits the synchronization between these cells, and abolishes oscillatory activity in acinar cells. We discuss possible mechanisms leading to the observed phenomena.

scholarly journals Dual Mode of Action of Acetylcholine on Cytosolic Calcium Oscillations in Pancreatic Beta and Acinar Cells in Situ

2021 ◽  
Author(s):  
Nastja Sluga ◽  
Sandra Postic ◽  
Srdjan Sarikas ◽  
Ya-Chi Huang ◽  
Andraz Stožer ◽  
...  
Keyword(s):  
Beta Cells ◽  
Acinar Cells ◽  
Cell Types ◽  
Cytosolic Calcium ◽  
Calcium Oscillations ◽  
The Body ◽  
Cholinergic Innervation ◽  
Oscillatory Activity ◽  
Tissue Slices

Cholinergic innervation in pancreas controls both the release of digestive enzymes to support the intestinal digestion and absorption, as well as insulin release to promote nutrient use in the cells of the body. The effects of muscarinic receptor stimulation are described in detail for endocrine beta cells and exocrine acinar cells separately. Here we describe morphological and functional criteria to separate these two cell types in situ in tissue slices and simultaneously measure their response to ACh stimulation on cytosolic Ca2+ oscillations [Ca2+]c in stimulatory glucose conditions. Our results show that both cell types respond to glucose directly in the concentration range compatible with the glucose transporters they express. The physiological ACh concentration increases the frequency of glucose stimulated [Ca2+]c oscillations in both cell types and synchronizes [Ca2+]c oscillations in acinar cells. The pharmacological ACh concentration further increases the oscillation frequency on the level of individual beta cells, inhibits the synchronization between these cells, and abolishes oscillatory activity in acinar cells. We discuss possible mechanisms leading to the observed phenomena.

scholarly journals Gnrh1-induced responses are indirect in female medaka Fsh cells

2019 ◽  
Author(s):  
Kjetil Hodne ◽  
Romain Fontaine ◽  
Eirill Ager-Wick ◽  
Finn-Arne Weltzien
Keyword(s):  
Patch Clamp ◽  
Adult Female ◽  
Reproductive Function ◽  
Cell Types ◽  
Gonadal Development ◽  
Pituitary Cells ◽  
Tissue Slices ◽  
Lh Cells ◽  
Different Cell Types

ABSTRACTReproductive function in vertebrates is stimulated by gonadotropin-releasing hormone (GnRH) that controls the synthesis and release of the two pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH). FSH and LH, which regulates different stages of gonadal development, are produced by two different cell types in the fish pituitary, in contrast to mammals and birds, thus allowing the investigation of their differential regulation. In the present work, we show by fluorescentin situhybridization that Lh cells in adult female medaka express Gnrh receptors, whereas Fsh cells do not. This is confirmed by patch clamp recordings and cytosolic Ca2+measurements on dispersed pituitary cells, where Lh cells, but not Fsh cells, respond to Gnrh1 by increased action potential frequencies and cytosolic Ca2+levels. In contrast, both Fsh and Lh cells are able to respond electrically and by elevating the cytosolic Ca2+levels to Gnrh1 in brain-pituitary tissue slices. Using Ca2+uncaging in combination with patch clamp recordings and cytosolic Ca2+measurements, we show that Fsh and Lh cells form homo- and heterotypic networks in the pituitary. Taken together, these results show that the effects of Gnrh1 on Fsh release in adult female medaka is indirect, likely mediated via Lh cells.

Ultrastructural analysis of VIP internalization in rat beta- and acinar cells in situ

1989 ◽  
Vol 256 (4) ◽  
pp. G689-G697
Author(s):  
A. Anteunis ◽  
A. Astesano ◽  
B. Portha ◽  
G. Hejblum ◽  
G. Rosselin
Keyword(s):  
High Resolution ◽  
Cell Surface ◽  
Beta Cells ◽  
Specific Activity ◽  
Acinar Cells ◽  
Volume Density ◽  
Computer Assisted ◽  
Assisted Analysis ◽  
Vacuolar System

We perfused the pancreas with 125I-labeled vasoactive intestinal peptide (VIP) to follow the concomitant distribution of radioactivity in beta- and acinar cells as a function of time. This distribution was quantitated by computer-assisted analysis of high-resolution video autoradiographs. Density labeling was expressed as normalized specific activity (disintegration density per volume density). Immediately after a 4-min perfusion of 125I-VIP, labeling in beta-cells was mainly concentrated on the cell surface and peripheral tubules and vesicles. After three 30-s pulses of 125I-VIP, separated by intervals of 3.5 min of buffer perfusion, lysosome-like structures were heavily labeled. When VIP internalization was prolonged, labeling was similar to that observed with the 4-min perfusion, indicating a high VIP disposal rate in the lysosome-like structures. In acinar cells, labeling persisted on the surface and the early vacuolar system. We conclude the following: 1) an active endocytotic system, linked to the transport and sorting of a neuromediator, is present in beta-cells; and 2) the differences between the distribution of labeling in acinar and beta-cells suggest that the regulation of VIP internalization is tissue specific.

scholarly journals The absence of H-2 antigens from mouse pancreatic beta-cells demonstrated by immunoferritin labeling.

1979 ◽  
Vol 150 (1) ◽  
pp. 1-9 ◽  
Author(s):  
E L Parr
Keyword(s):  
Endothelial Cells ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Beta Cell ◽  
Pancreatic Duct ◽  
Beta Cells ◽  
Pancreatic Beta Cells ◽  
Acinar Cells ◽  
Cell Types ◽  
Capillary Endothelial Cells

Islets of Langerhans were isolated from mouse pancreases and fixed in periodatelysine-paraformaldehyde. The fixed islets were then dissociated with trypsin and EDTA to yield cell suspensions that contained mainly four cell types; beta-cells, capillary endothelial cells, acinar cells, and pancreatic duct epithelial cells. The nonislet cells were probably associated wtih the surface of the isolated islets. The H-2 antigens of the dissociated pancreatic cells were labeled with an immunoferritin technique. Pancreatic duct epithelial cells showed specific ferritin labeling on their lateral cell membranes but not on apical microvillus membranes. Acinar cells were also labeled on lateral membranes, and the capillary endothelial cells were labeled on both the luminal and albuminal aspects of their surface membranes. In contrast, pancreatic beta-cells were unlabeled. The number of ferritin molecules per unit length of beta-cell membrane was essentially the same on cells from the antigenic strain and the congeneic control strain, and was about 200-fold less than on the labeled pancreatic duct epithelial cell lateral membranes. Pancreatic beta-cells are therefore one of six known epithelial cell types on which H-2 antigens can not be detected by immunoferritin labeling. The apparent absence of H-2 antigens from these cells suggests a study of the viability of beta-cells in allografts of dissociated islet cells, in which the beta-cell would not be in contact with antigenic cells. Such studies might lead to a new approach to the control of diabetes mellitus by transplantation.

scholarly journals Expression of Membrane-associated Mucins MUC1 and MUC4 in Major Human Salivary Glands

2002 ◽  
Vol 50 (6) ◽  
pp. 811-820 ◽  
Author(s):  
Bing Liu ◽  
Jessica R. Lague ◽  
David P. Nunes ◽  
Paul Toselli ◽  
Frank G. Oppenheim ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Salivary Glands ◽  
Acinar Cells ◽  
Cell Types ◽  
Northern Blotting ◽  
Submandibular Glands ◽  
Human Genes ◽  
Mucin Layer ◽  
Different Cell Types

Mucins are high molecular weight glycoproteins secreted by salivary glands and epithelial cells lining the digestive, respiratory, and reproductive tracts. These glyco-proteins, encoded in at least 13 distinct human genes, can be subdivided into gel-forming and membrane-associated forms. The gel-forming mucin MUC5B is secreted by mucous acinar cells in major and minor salivary glands, but little is known about the expression pattern of membrane-associated mucins. In this study, RT-PCR and Northern blotting demonstrated the presence of transcripts for MUC1 and MUC4 in both parotid and submandibular glands, and in situ hybridization localized these transcripts to epithelial cells lining striated and excretory ducts and in some serous acinar cells. The same cellular distribution was observed by immunohistochemistry. Soluble forms of both mucins were detected in parotid secretion after immunoprecipitation with mucin-specific antibodies. These studies have shown that membrane-associated mucins are produced in both parotid and submandibular glands and that they are expressed in different cell types than gel-forming mucins. Although the function of these mucins in the oral cavity remains to be elucidated, it is possible that they both contribute to the epithelial protective mucin layer and act as receptors initiating one or more intracellular signal transduction pathways.

scholarly journals Independently paced calcium oscillations in progenitor and differentiated cells in an ex vivo epithelial organ

2021 ◽  
Author(s):  
Anna Kim ◽  
Amanda Nguyen ◽  
Marco Marchetti ◽  
Denise Montell ◽  
Beth Pruitt ◽  
...  
Keyword(s):  
Stem Cells ◽  
Ex Vivo ◽  
Cell Types ◽  
Cytosolic Calcium ◽  
Calcium Oscillations ◽  
Enteroendocrine Cells ◽  
Calcium Dynamics ◽  
Differentiated Cells ◽  
Different Cell Types

Cytosolic calcium is a highly dynamic, tightly regulated, and broadly conserved cellular signal. Calcium dynamics have been studied widely in cellular monocultures, yet in vivo most organs comprise heterogeneous populations of stem and differentiated cells. We examined calcium dynamics in each cell type of the adult Drosophila intestine, a self-renewing epithelial organ where multipotent stem cells give rise to mature absorptive enterocytes and secretory enteroendocrine cells. Here we perform live imaging of whole organs ex vivo, and we employ orthogonal expression of red and green calcium sensors to determine whether calcium oscillations between different cell types are coupled. We show that stem cell daughters adopt strikingly distinct patterns of calcium oscillations when they acquire their terminal fates: enteroendocrine cells exhibit single-cell calcium oscillations, while long-range calcium waves propagate rhythmically across large fields of enterocytes. These multicellular waves do not propagate through progenitor cells (stem cells and undifferentiated enterocyte precursors), whose oscillation frequency is approximately half that of enteroendocrine cells. Organ-scale inhibition of gap junctions eliminates calcium oscillations in all three cell types, even, intriguingly, in progenitor and enteroendocrine cells that are surrounded only by enterocytes. Our findings establish that cells adopt fate-specific modes of calcium dynamics as they terminally differentiate and reveal that the oscillatory dynamics of different cell types in the same epithelium are paced independently.

Endothelial cells in human cytomegalovirus infection: One host cell out of many or a crucial target for virus spread?

2009 ◽  
Vol 102 (12) ◽  
pp. 1057-1063 ◽  
Author(s):  
Christian Sinzger ◽  
Barbara Adler
Keyword(s):  
Endothelial Cells ◽  
Human Cytomegalovirus ◽  
Cell Types ◽  
The Body ◽  
Cell Type ◽  
Cell Culture Systems ◽  
Human Cytomegalovirus Infection ◽  
Productive Replication

SummaryEndothelial cells (EC) are assumed to play a central role in the spread of human cytomegalovirus (HCMV) throughout the body. Results from in-situ analyses of infected tissues and data from cell culture systems together strongly suggest that vascular EC can support productive replication of HCMV and thus contribute to its haematogeneous dissemination. By inducing an angiogenic response, HCMV may even promote growth of its own habitat. The particular role of EC is further supported by the fact that entry of HCMV into EC is dependent on a complex of the envelope glycoproteins gH and gL with a set of proteins (UL128–131A) which is dispensable for HCMV entry into most other cell types. These molecular requirements may also be reflected by cell type-dependent differences in entry routes, i.e. endocytosis versus fusion at the plasma membrane. An animal model with trackable murine CMV is now available to clarify the pathogenetic role of EC during haematogeneous dissemination of this virus.

scholarly journals Glucose-dependent activation, activity, and deactivation of beta cell networks in acute mouse pancreas tissue slices

2020 ◽  
Author(s):  
Jurij Dolenšek ◽  
Maša Skelin Klemen ◽  
Marko Gosak ◽  
Lidija Križančić-Bombek ◽  
Viljem Pohorec ◽  
...  
Keyword(s):  
Beta Cell ◽  
Beta Cells ◽  
Insulin Release ◽  
Glucose Concentration ◽  
Calcium Oscillations ◽  
Tissue Slices ◽  
Mouse Pancreas ◽  
Network Parameters ◽  
Cell Networks ◽  
Glucose Dependence

AbstractGlucose progressively stimulates insulin release over a wide range of concentrations. However, the nutrient coding underlying activation, activity, and deactivation of beta cells affecting insulin release remains only partially described. Experimental data indicate that nutrient sensing in coupled beta cells in islets is predominantly a collective trait, overriding to a large extent functional differences between cells. However, some degree of heterogeneity between coupled beta cells may play important roles. To further elucidate glucose-dependent modalities in coupled beta cells, the degree of functional heterogeneity, and uncover the emergent collective operations, we combined acute mouse pancreas tissue slices with functional multicellular calcium imaging. We recorded beta cell calcium responses from threshold (7 mM) to supraphysiological (16 mM) glucose concentrations with high spatial and temporal resolution. This enabled the analysis of both classical physiological parameters and complex network parameters, as well as their comparison at the level of individual cells. The activation profile displayed two major glucose concentration-dependent features, shortening of delays to initial activation, and shortening of delays until half activation with increasing glucose concentration. Inversely, during deactivation both delays to initial deactivation and until half deactivation were progressively longer with increasing glucose concentration. The plateau activity with fast calcium oscillations expressed two types of glucose-dependence. Physiological concentrations mostly affected the frequency of oscillations, whereas supraphysiological concentrations progressively prolonged the duration of oscillations. Most of the measured functional network parameters also showed clear glucose-dependence. In conclusion, we propose novel understanding for glucose-dependent coding properties in beta cell networks, and its deciphering may have repercussions for our understanding of the normal physiology of glucose homeostasis as well as of disturbances of metabolic homeostasis, such as diabetes mellitus.

scholarly journals Using MERSCOPE to Generate a Cell Atlas of the Mouse Brain that Includes Lowly Expressed Genes

2021 ◽  
Vol 29 (6) ◽  
pp. 16-19
Author(s):  
George Emanuel ◽  
Jiang He
Keyword(s):  
Neural Circuits ◽  
Cell Types ◽  
The Body ◽  
A Cell ◽  
Health And Disease ◽  
Signaling Receptors ◽  
Spatial Positioning ◽  
The Brain ◽  
Resolution Cell

Abstract:The structure and organization of cells within organs is essential to their function, but nowhere in the body is this more spectacular than the brain. There, sprawling, snowflake-like neurons have grown into a precise arrangement, reaching out to neighboring cells to form neural circuits. Communication within neural circuits, made possible by spatial positioning, forms the basis of our physiology. Recently, a high-resolution cell atlas generated by MERFISH (multiplex error-robust fluorescence in situ hybridization) technology has mapped this spectacular organ with unmatched resolution, depth, and scale. The atlas catalogs cells as they exist in the intact biological system and will allow us to learn more about rare cell types and sparsely expressed cell signaling receptors fundamental to health and disease.

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