Diabetes-induced changes in cardiac voltage-gated ion channels

Table 1 Overview of diabetes mellitus-induced alterations in cardiac K⁺ currents

Diabetes Mellitus Type	Duration	Transient outward K+ currents		Delayed rectifier K+ currents		Inward rectifier K+ currents	Ref.
		Ito	Iss	IKr	IKs	IK1
Type 1	≤ 4 wk	↓	↓	?	↓	↔	[20,45,49,50,54,72,73,143-145]
	4-8 wk	↓	↓	↓↔	↓	↔	[19,21,29,40-43]
	> 8 wk	↓	↔	↓↔	↓	↓↔	[51,52,69]
Type 2		↓	↓	?	↓	↔	[30,39,49]

Table 2 Changes in L-type Ca²⁺ and Na⁺ currents in diabetic heart myocytes

Diabetes Mellitus Type	Duration	Ca2+ currents	Ref.	Na+ currents		Ref.
		ICaL		INa	INa,L
Type 1	≤ 4 wk	↔	[50]	↔	?	[130]
	4-8 wk	↓↔	[29,99,101-103,108]	↓	?	[130,132]
	> 8 wk	↓↔	[52,98]	↔↓	?	[69]
Type 1 transgenic		↓	[104]	?	↑	[135]
Type 2		↓	[89,105-108]	?	↑	[135]