OBJECTIVETo explore the biological effects of infrasound on the polygonal cells in adrenal cortex zona fasciculation in mice.

METHODSThe biological effects of infrasound on the activities of 3beta hydroxysteroid dehydrogenase (3-betaHSDH) and acid phosphatase(ACP) of the polygonal cells in adrenal cortex zona fasciculate were observed when exposure to 8 and 16 Hz infrasound at 80, 90, 100, 110, 120 and 130 dB for 1 day, 7 days and 14 days or 14 days after the exposure.

RESULTSWhen exposure to 8 Hz infrasound, the enzyme activities of 3-betaHSDH increase as the sound pressure levels increase. Only when the sound pressure levels reach 130 dB, the enzyme activities began to decrease exceptionally. When exposure to 16 Hz, 80 dB infrasound, no significant difference between the treatment and control group in the activities of 3-betaHSDH could be observed, but the injury of the polygonal cells had appeared. When exposure to 16 Hz, 100 dB infrasound, the activities of 3-betaHSDH started to increase. The cell injury still existed. When exposed to 16 Hz, 120 dB infrasound, the local tissue damage represented. Fourteen days after the mice exposure to 8 Hz, 90 dB and 130 dB infrasound for 14 days continuously, the local tissue injury of the adrenal cortex zona fasciculation began to recover at certain extent, but the higher the exposure sound pressure level, the poorer the tissue recovery.

CONCLUSIONThe biological effects of infrasound on the polygonal cells in adrenal cortex zona fasciculation response to the frequency of the infrasound are found at certain action strength range, but this characteristic usually is covered by the severe tissue injury. When exposure to infrasound is stopped for a period of time, the local tissue injury of the adrenal cortex zona fasciculation could recovers at certain extent, but the higher the exposure sound pressure level, the more poorer the tissue recovery.