Sasaki K, Nagao T
Department of Veterinary and Medical Science, Tokyo University of Agriculture and Technology, Fuchu, 183-8509, Tokyo, Japan
J Insect Physiol. 2001 Sep;47(10):1205-1216. doi: 10.1016/s0022-1910(01)00105-6.
To explore the role of dopamine and its metabolites for change of reproductive states of workers in honeybees (Apis mellifera), brain levels of dopamine relative substances were measured and localized in both normal workers and queenless workers. Dopamine and two possible metabolites of dopamine, N-acetyldopamine (NADA) and norepinephrine were detected in brain extracts. The brain levels of dopamine, NADA and norepinephrine were positively correlated with ovary development. Individuals with high dopamine levels had high levels of NADA or norepinephrine, suggesting that these metabolites might be involved in the change of reproductive sates of workers. Dopamine was distributed mainly in the protocerebrum, whereas NADA was in both the optic lobes and the protocerebrum. Dopamine levels in each distinct brain regions were higher in queenless workers than in normal workers, whereas there was a higher NADA level in the optic lobes in queenless workers than in normal workers. These results suggest that dopamine might be stored and/or released around the protocerebrum and the deutocerebrum, and also diffuse to the optic lobes where dopamine secretory cells are absent, resulting in high NADA levels in the optic lobes. The different manner of level changes of dopamine and its metabolites in each brain region might cause compound behavioural modulations in reproductive workers.
为探究多巴胺及其代谢产物在蜜蜂（西方蜜蜂）工蜂生殖状态变化中的作用，我们测定并定位了正常工蜂和失王工蜂大脑中多巴胺相关物质的水平。在脑提取物中检测到了多巴胺以及多巴胺的两种可能代谢产物，即N-乙酰多巴胺（NADA）和去甲肾上腺素。多巴胺、NADA和去甲肾上腺素的脑内水平与卵巢发育呈正相关。多巴胺水平高的个体，其NADA或去甲肾上腺素水平也高，这表明这些代谢产物可能参与了工蜂生殖状态的变化。多巴胺主要分布在原脑，而NADA在视叶和原脑中均有分布。失王工蜂各不同脑区的多巴胺水平高于正常工蜂，而失王工蜂视叶中的NADA水平高于正常工蜂。这些结果表明，多巴胺可能在原脑和中脑周围储存和/或释放，并且扩散到没有多巴胺分泌细胞的视叶，导致视叶中NADA水平升高。多巴胺及其代谢产物在每个脑区的水平变化方式不同，可能会导致生殖工蜂出现复合行为调节。
