description
Pancreatic beta cells are specialised endocrine cells that continuously sense the levels of blood sugar and other fuels and, in response, secrete insulin to maintain normal fuel homeostasis. Glucose-induced insulin secretion and its potentiation constitute the principal mechanism of insulin release. Glucose is transported by the glucose transporter (GLUT) into the pancreatic beta-cell. Metabolism of glucose generates ATP, which inhibits ATP-sensitive K+ channels and causes voltage-dependent Ca2+ influx. Elevation of [Ca2+]i triggers exocytotic release of insulin granules. Insulin secretion is further regulated by several hormones and neurotransmitters. Peptide hormones, such as glucagon-like peptide 1 (GLP-1), increase cAMP levels and thereby potentiate insulin secretion via the combined action of PKA and Epac2. Achetylcholine (ACh), a major parasympathetic neurotransmitter, binds to Gq-coupled receptors and activates phospholipase C- (PLC-), and the stimulatory effects involve activation of protein kinase C (PKC), which stimulates exocytosis. In addition, ACh mobilizes intracellular Ca2+ by activation of IP3 receptors
external resources
NCBI:777534
KEGG:hsa04911
PUBMED:9715374
PUBMED:10605628
PUBMED:9914469
PUBMED:17306374
PUBMED:20055708
PUBMED:15655710
PUBMED:19817784
PUBMED:19074620
PUBMED:14693691
PUBMED:17084085
PUBMED:20551594
PUBMED:19036624
PUBMED:22970724
PUBMED:20225132
PUBMED:19817800
PUBMED:22974438
PUBMED:21934040
PUBMED:15271645
PUBMED:19660440
PUBMED:11522660
genes
ADCY1
,
ADCY2
,
ADCY3
,
ADCY5
,
ADCY6
,
ADCY7
,
ADCY8
,
ADCY9
,
ADCYAP1
,
ADCYAP1R1
,
ATF4
,
ATP1A1
,
ATP1A2
,
ATP1A3
,
ATP1A4
,
ATP1B1
,
ATP1B2
,
ATP1B3
,
FXYD2
,
CACNA1C
,
CACNA1D
,
CACNA1F
,
CACNA1S
,
CAMK2A
,
CAMK2B
,
CAMK2D
,
CAMK2G
,
CCKAR
,
CHRM3
,
CREB1
,
ATF2
,
ATF6B
,
GCG
,
GCK
,
GIP
,
GLP1R
,
GNA11
,
GNAQ
,
GNAS
,
FFAR1
,
INS
,
PDX1
,
ITPR3
,
KCNJ11
,
KCNMA1
,
KCNMB1
,
KCNN1
,
KCNN2
,
KCNN3
,
KCNN4
,
PLCB2
,
PLCB3
,
PLCB4
,
PRKACA
,
PRKACB
,
PRKACG
,
PRKCA
,
PRKCB
,
PRKCG
,
RAB3A
,
RYR2
,
SLC2A1
,
SLC2A2
,
SNAP25
,
STX1A
,
ABCC8
,
VAMP2
,
CREB5
,
RIMS2
,
KCNMB2
,
CREB3
,
RAPGEF4
,
PLCB1
,
ATP1B4
,
KCNMB3
,
KCNMB4
,
PCLO
,
TRPM4
,
CREB3L2
,
CREB3L3
,
CREB3L1
,
GPR119
,
CREB3L4
,
KCNU1
,
ADCY4
,