Measurement of Spontaneous Oscillatory Magnetic Field of Guinea-Pig Smooth Muscle Preparation Using Pico-Tesla Resolution Amorphous Wire Magneto-Impedance Sensor

New measured results of spontaneous oscillatory bio-magnetic field generated from preparations of guinea-pig smooth muscle tissue are presented in this paper using the pico-Tesla MI sensor. It is confirmed that the changes in the bio-magnetic field activity precisely synchronized with extracellular electric activity for stomach musculature of the guinea-pig. It is, however, noteworthy that these two activities provide different biological information. A phase lag of around 2 s of the magnetic signal pulse against the extracellular electric signal pulse is newly found. It is also shown that Ca²⁺ channel activity of the smooth muscle tissue (taenia caeci) can be evaluated using the MI sensor. Both electric and magnetic activities depend on the functionality of the living tissues. Therefore, the pico-Tesla MI sensor has the potential for non-invasive detection use in wide range of biology and medicine, including non-invasive evaluation use of the stem cells development.