Thiele G, Holtorf A, Steinlechner S, Reiter R J
Life Sci. 1983 Oct 17;33(16):1543-7. doi: 10.1016/0024-3205(83)90694-x.
Wild-captured cotton rats (Sigmodon hispidus) trapped and tested in September and October exhibited a rapid reduction in pineal N-acetyltransferase (NAT) activity and melatonin levels after exposure to a light irradiance of 300 microW/cm2 during the dark period. The half-time for the depression of both NAT and melatonin was on the order of 2 min. The exposure of cotton rats during darkness to much lower irradiances of light, i.e., 5.0, 0.04, 0.03 or 0.01 W/cm2, for 32 min also greatly diminished pineal NAT activity and radioimmunoassayable melatonin levels; however, a light irradiance of 0.005 microW/cm2 failed to significantly depress either the acetylating enzyme or the melatonin content of the pineal gland. The results show that the pineal gland of the wild-captured cotton rat, as judged by NAT activity and melatonin levels, is inhibited even by very low irradiances of light.
在9月和10月捕获并进行测试的野生棉鼠，在黑暗期暴露于300微瓦/平方厘米的光照强度后，松果体N - 乙酰转移酶（NAT）活性和褪黑素水平迅速下降。NAT和褪黑素降低的半衰期约为2分钟。棉鼠在黑暗中暴露于更低的光照强度，即5.0、0.04、0.03或0.01瓦/平方厘米，持续32分钟，也会大大降低松果体NAT活性和放射免疫法可检测的褪黑素水平；然而，0.005微瓦/平方厘米的光照强度未能显著降低松果体的乙酰化酶或褪黑素含量。结果表明，从NAT活性和褪黑素水平判断，即使是非常低的光照强度也会抑制野生捕获棉鼠的松果体。
