Rauza Sukma Rita and Katsuya Dezaki and Yuko Maejima and Toshihiko Yada
Effect of Oxytocin on Cytosolic Calcium Concentration of Alpha and Beta Cells in Pancreas
135 - 138
2017
11
3
International Journal of Biomedical and Biological Engineering
https://publications.waset.org/pdf/10006742
https://publications.waset.org/vol/123
World Academy of Science, Engineering and Technology
Oxytocin is a nineamino acid peptide synthesized in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus. Oxytocin promotes contraction of the uterus during birth and milk ejection during breast feeding. Although oxytocin receptors are found predominantly in the breasts and uterus of females, many tissues and organs express oxytocin receptors, including the pituitary, heart, kidney, thymus, vascular endothelium, adipocytes, osteoblasts, adrenal gland, pancreatic islets, and many cell lines. On the other hand, in pancreatic islets, oxytocin receptors are expressed in both αcells and βcells with stronger expression in α cells. However, to our knowledge there are no reports yet about the effect of oxytocin on cytosolic calcium reaction on α and βcell. This study aims to investigate the effect of oxytocin on αcells and βcells and its oscillation pattern. Islet of Langerhans from wild type mice were isolated by collagenase digestion. Isolated and dissociated single cells either αcells or βcells on coverslips were mounted in an open chamber and superfused in HKRB. Cytosolic concentration (Ca2i) in single cells were measured by fura2 microfluorimetry. After measurement of Ca2i, αcells were identified by subsequent immunocytochemical staining using an antiglucagon antiserum. In βcells, the Ca2i increase in response to oxytocin was observed only under 8.3 mM glucose condition, whereas in αcells, Ca2i an increase induced by oxytocin was observed in both 2.8 mM and 8.3 mM glucose. The oscillation incidence was induced more frequently in βcells compared to αcells. In conclusion, the present study demonstrated that oxytocin directly interacts with both αcells and βcells and induces increase of Ca2i and its specific patterns.
Open Science Index 123, 2017