Insulin responsiveness to glucose of isolated islets of Langerhans was studied in 'younger' and 'older' rats after feeding and fasting for various lengths of time. In 'younger' rats, after prolonged fasting (168 h) the threshold for glucose-stimulated insulin secretion was increased. This was not evident in islets from 'younger' rats fasted for 48 or 89 h. Reductions in increments of insulin secretion with increments in glucose, in the maximum insulin secreted and in the total extractable insulin of the islets were apparent after fasting for 48, 89 and 168 h as compared with islets from fed rats. In 'older' rats, prolonged fasting caused an increase in the threshold for glucose-stimulated insulin secretion, reduced incremental insulin secretion, reduced maximum insulin secretion and reduced total extractable insulin. However, the responses of islets from fed 'older' rats were similar to those of fasted (168 h) 'younger' rats. The threshold levels were similar, and there were no significant differences between increments in insulin secretion, maximum insulin secretion and insulin content of the islets. These experiments show that the responsiveness of islets of Langerhans in rats can be altered by age and fasting.
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http://dx.doi.org/10.1139/y75-100 | DOI Listing |
J Pediatr Endocrinol Metab
January 2025
Department of Paediatrics, School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
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UR Diabète et Thérapeutiques, Centre européen d'étude du Diabète, Université de Strasbourg, Strasbourg, France.
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View Article and Find Full Text PDFSci China Life Sci
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State Key Laboratory of Pharmaceutical Biotechnology, Department of Endocrinology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Model Animal Research Center, Nanjing University, Nanjing, 210061, China.
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View Article and Find Full Text PDFEndocr J
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Department of Molecular Diagnosis, Chiba University Graduate school of Medicine, Chiba 260-8670, Japan.
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