绿蟾蜍和食用蛙视网膜、松果体及哈德氏腺褪黑素分泌的比较研究

A comparative study of melatonin production in the retina, pineal gland and harderian gland of Bufo viridis and Rana esculenta.

Serino I, d'Istria M, Monteleone P

Dipartimento di Fisiologia Umana e Funzioni Biologiche Integrate Filippo Bottazzi, Seconda Università degli Studi di Napoli, Naples, Italy.

Comp Biochem Physiol C Comp Pharmacol Toxicol. 1993 Sep;106(1):189-93. doi: 10.1016/0742-8413(93)90271-l.

Abstract

The circadian patterns of melatonin and of its synthesizing enzyme N-acetyltransferase (NAT) were investigated in the serum, retina, pineal gland and Harderian gland (HG) of two amphibian species, Bufo viridis and Rana esculenta. 2. Serum melatonin levels showed no diurnal fluctuations in Bufo viridis, whereas, in Rana esculenta, they exhibited a circadian rhythm, with the highest values occurring during the night. Retina melatonin exhibited characteristic circadian patterns in both species, with the highest values occurring during the day, in Bufo, and the highest concentrations occurring at night in Rana. 3. In the retina, NAT activity peaked at night in both amphibians, but in Bufo the levels were up to 30 times higher than in Rana. In the HG and in the pineal gland, NAT activity showed different patterns in the two species with no diurnal variations in Bufo, and characteristic circadian rhythms in Rana. 4. In the HG and pineal gland of both species, melatonin was only occasionally detectable over the 24-hr period. 5. This is the first report exploring melatonin production in Bufo viridis and Rana esculenta. In our experimental conditions, marked differences emerged between the two species.

摘要

研究了绿蟾蜍和食用蛙这两种两栖动物血清、视网膜、松果体和哈德氏腺（HG）中褪黑素及其合成酶N - 乙酰转移酶（NAT）的昼夜节律模式。2. 绿蟾蜍血清褪黑素水平无昼夜波动，而食用蛙血清褪黑素水平呈现昼夜节律，夜间值最高。两种动物视网膜中的褪黑素均呈现出特征性的昼夜节律模式，绿蟾蜍白天的值最高，食用蛙夜间的浓度最高。3. 在视网膜中，两种两栖动物的NAT活性均在夜间达到峰值，但绿蟾蜍的水平比食用蛙高30倍。在哈德氏腺和松果体中，两种动物的NAT活性呈现不同模式，绿蟾蜍无昼夜变化，食用蛙有特征性的昼夜节律。4. 在两种动物的哈德氏腺和松果体中，24小时内仅偶尔能检测到褪黑素。5. 这是关于绿蟾蜍和食用蛙褪黑素产生的首次报道。在我们的实验条件下，两种动物之间出现了显著差异。