Several biogenic amines, including controversial presence of norepinephrine (NE), were identified by the high performance liquid chromatography equipped with electrospray ionisation mass spectrometry in brain complexes of adult females of Pyrrhocoris apterus. Quantitative analysis was performed by the high performance liquid chromatography coupled to electrochemical detector. Levels of NE, dopamine (DA), octopamine (OA) and 5-hydroxytryptamine (5-HT) in brain complexes were measured in reproductive vs. diapause females. In field collected samples, levels of NE and DA were significantly higher in reproductive (May) than in non-reproductive (Sep, Oct, Feb) females. In laboratory females, NE is higher in long day photoperiod (reproduction) than in short day photoperiod (diapause) already from the first week of the adult age, while DA shows differences between the two contrasting photoperiods only from the second week of the adult age. No association between reproductive status and levels of OA and 5-HT was found.

• MeSH
• Chromatography, Liquid MeSH
• Dopamine metabolism   MeSH
• Heteroptera metabolism   MeSH
• Spectrometry, Mass, Electrospray Ionization methods   MeSH
• Catecholamines metabolism   MeSH
• Brain metabolism   MeSH
• Norepinephrine metabolism   MeSH
• Octopamine metabolism   MeSH
• Seasons MeSH
• Reproduction MeSH
• Tilia parasitology   MeSH
• Animals MeSH
• Check Tag
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Current models state that insect peripheral oscillators are directly responsive to light, while mammalian peripheral clock genes are coordinated by a master clock in the brain via intermediate factors, possibly hormonal. We show that the expression levels of two circadian clock genes, period (per) and Par Domain Protein 1 (Pdp1) in the peripheral tissue of an insect model species, the linden bug Pyrrhocoris apterus, are inversely affected by contrasting photoperiods. The effect of photoperiod on per and Pdp1 mRNA levels was found to be mediated by the corpus allatum, an endocrine gland producing juvenile hormone. Our results provide the first experimental evidence for the effect of an endocrine gland on circadian clock gene expression in insects.

• MeSH
• Circadian Rhythm MeSH
• Endocrine System MeSH
• Financing, Organized MeSH
• Heteroptera genetics   MeSH
• Nuclear Proteins genetics   MeSH
• Gene Expression Regulation genetics   MeSH
• Trans-Activators genetics   MeSH
• Basic-Leucine Zipper Transcription Factors genetics   MeSH
• Animals MeSH
• Check Tag
• Female MeSH
• Animals MeSH