caa a22 4500 475848144 CHVBK 20180406123920.0 cr unu---uuuuu 170329e20000101xx s 000 0 eng 10.1007/PL00007505 doi (NATIONALLICENCE)springer-10.1007/PL00007505 Preventive effect of magnesium supplement on noise-induced hearing loss in the guinea pig [Elektronische Daten] [Fred Scheibe, H. Haupt, H. Ising] The effect of magnesium (Mg) on noise-induced hearing loss was investigated in two groups of adult pigmented guinea pigs maintained either on optimal or suboptimal (physiologically high or low) Mg produced by different diets. The total Mg concentrations of the perilymph (PL), cerebrospinal fluid, blood plasma and red blood cells were measured by atomic absorption spectrometry and were found to differ significantly between the two groups (P < 0.01). One ear of each animal was exposed to either a single shooting impulse at a peak pressure level of 187 dB or two impulse noise series at a rate of 1/s and peak pressure levels of 150 dB (1,000 impulses) and 167 dB (2,280 impulses), respectively. Temporary (TTS) and permanent (PTS) hearing threshold shifts in anesthetized animals were measured 2 h and 1 week after the noise exposure, using auditory brain stem response (ABR) audiometry at a frequency range from 3.75 to 30 kHz. Exposure to the single noise impulse resulted in a mean TTS that was significantly lower in the high Mg group than that in the low Mg group (P < 0.05), although no substantial PTS was observed in either group. In the animals exposed to 150 dB noise, the TTS showed a tendency towards an Mg-related reduction at the higher frequencies. A small difference in PTS was found between the low Mg and high Mg groups, but was not significant. Exposure to the 167-dB noise series caused a considerable TTS, which was significantly lower in the high Mg group at 7.5 and 15 kHz than in the low Mg group (P < 0.05). The mean PTS showed a significant difference between the two Mg groups over the whole frequency range (P < 0.05) and was found to correlate negatively with the total Mg concentrations of both PL and plasma (P < 0.05). Moreover, the high Mg group showed a faster recovery from the hearing threshold shift than the low Mg group. The present findings show that preventive oral Mg supplements can significantly reduce the rate of acoustic trauma caused by high-level impulse noise exposure in the guinea pig. Springer-Verlag Berlin Heidelberg, 2000 Key words Magnesium supplement nationallicence Impulse noise nationallicence Hearing loss nationallicence Auditory brain stem response testing nationallicence Guinea pig nationallicence Scheibe Fred Department of Otorhinolaryngology, Charité Hospital, Humboldt University, Schumannstrasse 20-21, 10117 Berlin, Germany e-mail: fred.scheibe@charite.de, Tel.: +49 30 2802 2764, Fax: +49 30 2802 4088, DE aut Haupt H. Department of Otorhinolaryngology, Charité Hospital, Humboldt University, Schumannstrasse 20-21, 10117 Berlin, Germany e-mail: fred.scheibe@charite.de, Tel.: +49 30 2802 2764, Fax: +49 30 2802 4088, DE aut Ising H. Institute for Water, Soil and Air Hygiene, The Federal Environment Agency, Corrensplatz 1, 14195 Berlin, Germany, DE aut https://doi.org/10.1007/PL00007505 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/PL00007505 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Scheibe Fred Department of Otorhinolaryngology, Charité Hospital, Humboldt University, Schumannstrasse 20-21, 10117 Berlin, Germany e-mail: fred.scheibe@charite.de, Tel.: +49 30 2802 2764, Fax: +49 30 2802 4088, DE aut NATIONALLICENCE 700 1- Haupt H. Department of Otorhinolaryngology, Charité Hospital, Humboldt University, Schumannstrasse 20-21, 10117 Berlin, Germany e-mail: fred.scheibe@charite.de, Tel.: +49 30 2802 2764, Fax: +49 30 2802 4088, DE aut NATIONALLICENCE 700 1- Ising H. Institute for Water, Soil and Air Hygiene, The Federal Environment Agency, Corrensplatz 1, 14195 Berlin, Germany, DE aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer