The application of cardiac assist devices has revealed that end-stage heart failure
can be reversed. In investigations on the myocardial level, the normalization of the
extracellular matrix function was found most important. Electrical microcurrent can
modulate the collagen composition (collagen I and III) of the extracellular matrix.
We investigated the effect of electrical microcurrent on cardiomyocytes under culture
conditions. The influence of low (50µA) and high (100µA) microcurrent on cultured
cardiomyocytes from adult rats was compared to cultured cardiomyocytes without application
of microcurrent (control). Changes in the cell proliferation; collagen I, III; in
MMP 2, 3, 8, 9, 13, 14, 16; TIMP 1, 2; IL-1, 6; TNF-α; TGF-β; GM-CSF; connexin 40,
43, 45 were measured. After 90h of cultivation, compared to the control cultured cardiomyocytes
proliferation increased by 70% under low microcurrent application. Collagen I synthesis
decreased by 35% (low microcurrent) and collagen III increased by 100% (high microcurrent).
The MMPs (3, 8, 9, 16) expression showed a significant decrease at high microcurrent
application. The TIMPs remained unaffected. IL-6 was suppressed by high microcurrent.
TNF-α, IL-1 and GM-CSF were not detected at all. High microcurrent leads to a reduced
IL-6 and TGF-β expression. As sign for the viability and functionality of the myocytes
the connexin 40, 43, and 45 showed the most pronounced increase when stimulated by
low microcurrent. Microcurrent application on cardiomyocytes can influence the components
of the extracellular matrix. So it may be conceivable to influence the extracellular
matrix by electrical microcurrent to normalize their function.
