Dopamine, N-Acetyldopamine and Serotonin Concentrations in the Visual System of Praying Mantis During Postembryonic Development

Abstract

High-performance liquid chromatography with electrochemical detection was used to quantify the two biogenic amines dopamine (DA) and 5-hydroxytryptamine (5-HT, serotonin) as well as a metabolite of DA, N-acetyldopamine (NADA), in the compound eyes and optic lobes of praying mantis ( Polyspilota sp. and Tenodera sinensis) during postembryonic development. After hatching, DA and 5-HT concentrations (pmol/mg ww) were relatively high (DA, 5.43 ± 1.13; 5-HT, 5.65 ± 1.0 for Polyspilota), but the NADA concentration was more than 25 times higher than those of DA and 5-HT (143.7 ± 16.71 for Polyspilota). Subsequently, the concentrations decreased constantly into the middle larval instar and then rose to reach their highest peak in the last larval instar (DA) or a very high concentration in the seventh instar (5-HT and NADA). In adults, DA, 5-HT and NADA concentrations decreased again. The concentration profile for NADA was similar to that of 5-HT. The values per structure (compound eye and optic lobe complex) and per ommatidial column channel were also calculated. It is significant that changes in the amine levels during postembryonic development went hand in hand with development changes in the activity and behavior of the mantids.