Microanatomical changes in the pancreatic islet cells of streptozotocin induced diabetic Wistar rats were studied after treatment with methanolic extracts of Annona muricata leaves. Thirty adult Wistar rats were randomly assigned into three groups (control, untreated diabetic group, and A. muricata-treated diabetic group) of ten rats each. Diabetes mellitus was experimentally induced in groups ...

Islets of Langerhans are microorgans scattered throughout the pancreas, and are responsible for synthesizing and secreting pancreatic hormones. While progress has recently been made concerning cell differentiation of the islets of Langerhans, the mechanism controlling islet morphogenesis is not known. It is thought that these islets are formed by mature cell association, first differentiating i...

Neuropeptide Y (NPY), whose role in appetite regulation is well known, is also expressed in pancreatic islets. Although previous studies indicated that application of NPY to pancreatic islets inhibits insulin secretion, its physiological role in the regulation of insulin secretion is not fully understood. We hypothesized that NPY in islets tonically suppresses insulin secretion and the reductio...

The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, thus impacting glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are unknown, particularly in human. Here we demonstrate that the innervation of human islets is different from that of mouse islets and do...

Beta-cells inside the pancreatic islets of Langerhans are the only source of the hormone insulin. Visualization of pancreatic islets with MRI in the mouse has many potential applications in preclinical diabetes research, because the amount of beta-cells decreases with the onset of the disease. Islets of Langerhans were imaged with a beta-cell specific MRI contrast agent in the excised murine pa...

OBJECTIVE Pancreatic TRH is present in insulin-producing B-cells of the islets of Langerhans. There is fragmentary evidence that it may be involved in glucoregulation. The aim of our present study was to analyze how glucose and insulin affect TRH secretion by the pancreatic islets. DESIGN Isolated pancreatic islets were incubated with different concentrations of glucose, insulin and glucagon,...

The islets of Langerhans contain four distinct endocrine cell types producing the hormones glucagon, insulin, somatostatin and pancreatic polypeptide. These cell lineages are thought to arise from a common, multipotential progenitor cell whose identity has not been well established. The pancreatic and intestinal hormone, peptide YY, has been previously identified in glucagon-producing cells in ...

A polymorphism located in the G6PC2 gene, which encodes an islet-specific glucose-6-phosphatase catalytic subunit, is the most important common determinant of variations in fasting blood glucose (FBG) levels in humans. Studies of G6pc2 knockout (KO) mice suggest that G6pc2 represents a negative regulator of basal glucose-stimulated insulin secretion (GSIS) that acts by hydrolyzing glucose-6-pho...

BACKGROUND Hyperglycemia induces activation of the c-Jun N-terminal kinase (JNK) pathway, which suppresses insulin gene expression and reduces DNA binding of pancreatic and duodenal homeobox factor (PDX)-1. This study aims to investigate the effects of a novel curcumin derivative (NCD) on JNK signaling pathway on insulin synthesis and secretion in streptozotocin (STZ)-treated rat pancreatic isl...

Rozance PJ, Limesand SW, Zerbe GO, Hay WW Jr. Chronic fetal hypoglycemia inhibits the later steps of stimulus-secretion coupling in pancreatic -cells. Am J Physiol Endocrinol Metab 292: E1256 –E1264, 2007. First published January 9, 2007; doi:10.1152/ajpendo.00265.2006.—We measured the impact of chronic late gestation hypoglycemia on pancreatic islet structure and function to determine the caus...