Effects on pulsed magnetic field (PMF) contraction forces in Erugosquilla massavensis (Kossman,1880)(stomatopoda, crustacea) in muscle

The aim of this study was to determine the effects of the pulsed magnetic field (MF) on the isometric contractile characteristics of the lateral extensor muscles in raptorial claw of Erugosquilla massavensis (Kossman, 1880). Before, the experimental groups were divided into the two groups as a control (C) and magnetic field (MF). The E. massavensis in the PMF (MF) groups were exposed to the pulsed magnetic field at 50 Hz (1.5 mT intensity) for 2 h /30 days. At the end of 30 days experiment period Raptorial appendages (merus-carpus-propus segment) of E. massavensis were taken for biomechanical recordings. Muscle strips were taken from the merus segmet lateral extensor muscles of E. massavensis. Then it was recorded electron microscopy images of tissues taken from muscle preparations. Electron microscopy results showed the lateral extensor musle cells were affected by pulsed Magnetic Field. Control Groups were in normally physiological structure. Magnetic Filed Groups muscle samples were observed increase in peripheral hetrecromatin content in nuclei under the sarcolemma, expansion in the perinuclear cisterna and sweilling in the mitochondria in the sarcoplasma. When the mean biomechanical parameters were calculated, isometric contraction force mean of the control groups (Psarsı) 9.96±0.50 (mN), magnetic field groups (Psarsı) 8.35±0.55 (mN) were calculated. A statisctically significant difference was found between the isometric contraction force mean of the Control and MF groups. (P<0.05). The depolarization time (CT) was 129.20±12.61 ms in the control group and 109.20 ±10.11 ms in MA group; Half-Repolarization Time (1/2 RT) was 195.15±21.19 ms for the control group, 115.90±4.91 ms for the magnetic field group, 1/2RT:195.15±21.19. While positive contraction velocity (+dP/dt) 342.85±32.13 mNms and negative contraction velocity 178.65±17.89 mNms was calculated for the control group, the magnetic field group of the positive contraction rate (+dP/dt) 291.30±32.24 mNms, and the negative contraction rate as (-dP/dt) was 171.25±17.92 mNms. A statisctically significant difference was found between the Half-Repolarization Times of the Control and MF groups(P<0.05).