Page 80 - Biochemistry PharmD General
P. 80

Glucose action in the b-cell

                                       Glucose enters the b-cell as
                                       blood glucose concentration
                                       rises. Glycolysis to generate

                                         ATP closes K+ channels in
                                       the cell membrane, stopping

                                           outward transport, and
                                            opening Ca+ channels.
                                         Inward flux of Ca+ causes
                                            exocytosis of insulin-
                                            containing secretory
                                            vesicles. Glucose also
                                       stimulates synthesis of new

                                                      insulin.

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