title: Pulse-driven magnetoimpedance sensor detection of biomagnetic fields in musculatures with spontaneous electric activity.
abstract: We measured biomagnetic fields in musculatures with spontaneous electric activity using a pulse-driven magnetoimpedance (PMI) sensor with the sensitivity improved toward a pico-Tesla (pT) level. Due to the sufficiently short operation interval of 1 μs, this magnetic sensor enabled quasi-real time recordings of the magnetic field for biological electric activity. Isolated small musculatures from the guinea-pig stomach, taenia caeci, portal vein and urinary bladder were incubated in an organ bath at a body temperature. The improved PMI sensor mounted approximately 1mm below the preparations detected oscillatory magnetic fields reflecting spontaneous electric activities of musculature preparations. In the taenia caeci, application of tetraethyl ammonium (TEA), a K(+) channel blocker, significantly enhanced the magnetic activity estimated by histogram analysis. Also, in some musculature preparations, simultaneous measurements with electric activity revealed that the observed magnetic activities were attributed to biological electric activity. PMI technology is promising for applications in biology and medicine.
authors: Department of Cell Physiology, Nagoya University Graduate School of Medicine, Nagoya, Japan. h44673a@nucc.cc.nagoya-u.ac.jp
authors: Shinsuke
authors: S
authors: Nakayama
authors: Satoshi
authors: S
authors: Atsuta
authors: Takao
authors: T
authors: Shinmi
authors: Tsuyoshi
authors: T
authors: Uchiyama
mesh_terms: D000818:Animals; D017097:Electric Impedance; D004574:Electromagnetic Fields; D055724:Electrophysiological Phenomena; D006168:Guinea Pigs; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D026902:Potassium Channel Blockers / Q000494:pharmacology; D012680:Sensitivity and Specificity; D019789:Tetraethylammonium / Q000494:pharmacology
chemical_list: D026902:Potassium Channel Blockers; D019789:Tetraethylammonium