@misc{BlenauGrohmannErberetal.2003,
  author    = {Blenau, Wolfgang and Grohmann, Lore and Erber, Joachim and Ebert, Paul R. and Str{\"u}nker, Timo and Baumann, Arnd},
  title     = {Molecular and functional characterization of an octopamine receptor from honeybee (Apis mellifera) brain},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-44293},
  year      = {2003},
  abstract  = {Biogenic amines and their receptors regulate and modulate many physiological and behavioural processes in animals. In vertebrates, octopamine is only found in trace amounts and its function as a true neurotransmitter is unclear. In protostomes, however, octopamine can act as neurotransmitter, neuromodulator and neurohormone. In the honeybee, octopamine acts as a neuromodulator and is involved in learning and memory formation. The identification of potential octopamine receptors is decisive for an understanding of the cellular pathways involved in mediating the effects of octopamine. Here we report the cloning and functional characterization of the first octopamine receptor from the honeybee, Apis mellifera . The gene was isolated from a brain-specific cDNA library. It encodes a protein most closely related to octopamine receptors from Drosophila melanogaster and Lymnea stagnalis . Signalling properties of the cloned receptor were studied in transiently transfected human embryonic kidney (HEK) 293 cells. Nanomolar to micromolar concentrations of octopamine induced oscillatory increases in the intracellular Ca2+ concentration. In contrast to octopamine, tyramine only elicited Ca2+ responses at micromolar concentrations. The gene is abundantly expressed in many somata of the honeybee brain, suggesting that this octopamine receptor is involved in the processing of sensory inputs, antennal motor outputs and higher-order brain functions.},
  language  = {en}
}
@misc{BlenauTroppmannWalz2007,
  author    = {Blenau, Wolfgang and Troppmann, Britta and Walz, Bernd},
  title     = {Pharmacology of serotonin-induced salivary secretion in Periplaneta americana},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-44319},
  year      = {2007},
  abstract  = {The acinar salivary gland of the cockroach, Periplaneta americana, is innervated by dopaminergic and serotonergic nerve fibers. Stimulation of the glands by serotonin (5-hydroxytryptamine, 5-HT) results in the production of a protein-rich saliva, whereas stimulation by dopamine results in saliva that is protein-free. Thus, dopamine acts selectively on ion-transporting peripheral cells within the acini, and 5-HT acts on protein-producing central cells. We have investigated the pharmacology of the 5-HT-induced secretory activity of isolated salivary glands of P. americana by testing several 5-HT receptor agonists and antagonists. The effects of 5-HT can be mimicked by the non-selective 5-HT receptor agonist 5-methoxytryptamine. All tested agonists that display at least some receptor subtype specificity in mammals, i.e., 5-carboxamidotryptamine, (+/-)-8-OH-DPAT, (+/-)-DOI, and AS 19, were ineffective in stimulating salivary secretion. 5-HT-induced secretion can be blocked by the vertebrate 5-HT receptor antagonists methiothepin, cyproheptadine, and mianserin. Our pharmacological data indicate that the pharmacology of arthropod 5-HT receptors is remarkably different from that of their vertebrate counterparts. (C) 2007 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@misc{BlenauMustardHamiltonetal.2003,
  author    = {Blenau, Wolfgang and Mustard, Julie A. and Hamilton, Ingrid S. and Ward, Vernon K. and Ebert, Paul R. and Mercer, Alison R.},
  title     = {Analysis of two D1-like dopamine receptors from the honey bee Apis mellifera reveals agonist-independent activity},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-44378},
  year      = {2003},
  abstract  = {Dopamine is found in many invertebrate organisms, including insects, however, the mechanisms through which this amine operates remain unclear. We have expressed two dopamine receptors cloned from honey bee (AmDOP1 and AmDOP2) in insect cells (Spodoptera frugiperda), and compared their pharmacology directly using production of cAMP as a functional assay. In each assay, AmDOP1 receptors required lower concentrations of dopamine and 6,7-ADTN for maximal activation than AmDOP2 receptors. Conversely, butaclamol and cis(Z)-flupentixol were more potent at blocking the cAMP response mediated through AmDOP2 than AmDOP1 receptors. Expression of AmDOP1, but not AmDOP2, receptors significantly increased levels of cAMP even in the absence of ligand. This constitutive activity was blocked by cis(Z)-flupentixol. This work provides the first evidence of a constitutively activated dopamine receptor in invertebrates and suggests that although AmDOP1 and AmDOP2 share much less homology than their vertebrate counterparts, they display a number of functional parallels with the mammalian D1-like dopamine receptors.},
  language  = {en}
}