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Modeling of the gap junction of pancreatic β -cells and the robustness of insulin secretion

View Article: PubMed Central - PubMed

ABSTRACT

Pancreatic β-cells are interconnected by gap junctions, which allow small molecules to pass from cell to cell. In spite of the importance of the gap junctions in cellular communication, modeling studies have been limited by the complexity of the system. Here, we propose a mathematical gap junction model that properly takes into account biological functions, and apply this model to the study of the β-cell cluster. We consider both electrical and metabolic features of the system. Then, we find that when a fraction of the ATP-sensitive K+ channels are damaged, robust insulin secretion can only be achieved by gap junctions. Our finding is consistent with recent experiments conducted by Rocheleau et al. Our study also suggests that the free passage of potassium ions through gap junctions plays an important role in achieving metabolic synchronization between β-cells.

No MeSH data available.


Effect of the ḡCa variation. Original ḡCa value is 1000 pS.
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f17-6_37: Effect of the ḡCa variation. Original ḡCa value is 1000 pS.

Mentions: To investigate the role of gap junctions further, we studies the activity of the voltagegated Ca2+ channel by changing ḡCa values. The original ḡCa value is 1000 pS, and Fig. 14 shows the model calculations. We then changed the value of ḡCa from 1000 pS to 900 pS and 1100 pS. Their corresponding results are shown in Figs. 16 and 17, respectively. Two coupled β-cells are successfully synchronized via the gap junction, and a very similar result to that of the ḡCa =1000 pS case is produced (see Fig. 11(a) or Fig. 14) although original individual patterns are very different each other as shown in Figs. 16 and 17. This kind of character has been observed consistently in other tested cases including the three coupled β-cell system.


Modeling of the gap junction of pancreatic β -cells and the robustness of insulin secretion
Effect of the ḡCa variation. Original ḡCa value is 1000 pS.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC5036665&req=5

f17-6_37: Effect of the ḡCa variation. Original ḡCa value is 1000 pS.
Mentions: To investigate the role of gap junctions further, we studies the activity of the voltagegated Ca2+ channel by changing ḡCa values. The original ḡCa value is 1000 pS, and Fig. 14 shows the model calculations. We then changed the value of ḡCa from 1000 pS to 900 pS and 1100 pS. Their corresponding results are shown in Figs. 16 and 17, respectively. Two coupled β-cells are successfully synchronized via the gap junction, and a very similar result to that of the ḡCa =1000 pS case is produced (see Fig. 11(a) or Fig. 14) although original individual patterns are very different each other as shown in Figs. 16 and 17. This kind of character has been observed consistently in other tested cases including the three coupled β-cell system.

View Article: PubMed Central - PubMed

ABSTRACT

Pancreatic β-cells are interconnected by gap junctions, which allow small molecules to pass from cell to cell. In spite of the importance of the gap junctions in cellular communication, modeling studies have been limited by the complexity of the system. Here, we propose a mathematical gap junction model that properly takes into account biological functions, and apply this model to the study of the β-cell cluster. We consider both electrical and metabolic features of the system. Then, we find that when a fraction of the ATP-sensitive K+ channels are damaged, robust insulin secretion can only be achieved by gap junctions. Our finding is consistent with recent experiments conducted by Rocheleau et al. Our study also suggests that the free passage of potassium ions through gap junctions plays an important role in achieving metabolic synchronization between β-cells.

No MeSH data available.