Low-frequency electromagnetic pulses enhance Ca 2+ uptake by chick small intestine in vitro

Abstract

The effect of external EMF on Ca 2+ uptake by the chick small intestine was investigated in vitro by use of the accumulating preparations of epithelial tissue. The intestinal tissue preparations were exposed to EMF in specific zones of Helmholtz coils. The steady magnetic field (SMF) having an induction value B 0 = 1.14 mT, as well as pulsed EMF—constant pulse rate ( f = 80 Hz) and randomized pulse rate (in range of 40–120 Hz)—with amplitude B M = B 0 was used. The fall time of the pulse was changed stepwise in the range 0.15–0.55 ms. It was found that SMF, as well as pulsed EMF significantly enhanced the uptake of Ca 2+ by the small intestine. A SMF was found to enhance uptake by up to 40–50% for both normal (D) and rachitic chicks. The effects of the induced E rot depended essentially of vitamin D status of chicks due to the complex action of vitamin D-dependent factors. The effect of randomized pulse EMF was qualitatively similar to that of constant pulse EMF, but quantitatively it was less. Data indicate the contribution of the B-, as well as E-component to the modification of the Ca 2+ uptake.