TABLE 1

KATP channel-independent glucose action and the two phases of insulin secretion

SpeciesStatus of the KATP channelFirst phaseSecond phaseReference
Human
    PHHI*Closed (SUR1 mutation)+a(26)
    PHHIClosed (SUR1 mutation)ND+(27)
    NormalOpen (diazoxide)ND+(34)
Rat
    NormalClosed (tolbutamide)++(31)
    NormalOpen (diazoxide)+(12)
Mouse
    NormalClosed (glyburide)++(30)
    NormalClosed (glyburide or tolbutamide)++(32)
    KnockoutClosed (Kir6.2 knockout)TraceTrace(28)
    KnockoutClosed (SUR1 knockout)ND+(29)
    NormalOpen (diazoxide)+(13)
  • A list of the initial observations in which insulin secretion in response to glucose was reported in the β-cell with the KATP channels being closed or open by the gene mutation, pharmacological agents, or targeted disruption of the genes, as indicated in the parentheses. a, Likely due to decreased β-cell insulin content (27). ND, not determined.

  • *

    * This is an in vivo study where glucose was injected to the patients intravenously. Other studies were performed by using isolated pancreatic islets. Because existence of the first phase cannot be ascertained unless a perifusion experiment is performed, it was designated as ND when the perifusion was not done.