@article{BaumannKuehnelDamesetal.2004, author = {Baumann, Otto and K{\"u}hnel, Dana and Dames, Petra and Walz, Bernd}, title = {Dopaminergic and serotonergic innervation of cockroach salivary glands : distribution and morphology of synapses and release sites}, year = {2004}, abstract = {The paired salivary glands in the cockroach are composed of acini with ion-transporting peripheral P-cells and protein-secreting central C-cells, and a duct system for the modification of the primary saliva. Secretory activity is controlled by serotonergic and dopaminergic neurons, whose axons form a dense plexus on the glands. The spatial relationship of release sites for serotonin and dopamine to the various cell types was determined by anti-synapsin immunofluorescence confocal microscopy and electron microscopy. Every C-cell apparently has only serotonergic synapses on its surface. Serotonergic and dopaminergic fibres on the acini have their release zones at a distance of similar to0.5 mum from the P-cells. Nerves between acinar lobules may serve as neurohaemal organs and contain abundant dopaminergic and few serotonergic release sites. Some dopaminergic and serotonergic release sites reside in the duct epithelium, the former throughout the duct system, the latter only in segments next to acini. These findings are consistent with the view that C-cells respond exclusively to serotonin, P-cells to serotonin and dopamine, and most duct cells only to dopamine. Moreover, the data suggest that C-cells are stimulated by serotonin released close to their surface, whereas P-cells and most duct cells are exposed to serotonin/dopamine liberated at some distance}, language = {en} } @article{DamesSchmidtWalzetal.2004, author = {Dames, Petra and Schmidt, R. and Walz, Bernd and Baumann, Otto}, title = {Regulation of vacuolar-type H+-ATPase (vATPase) in blowfly salivary glands}, issn = {0171-9335}, year = {2004}, language = {en} } @article{SchmidtWalz2004, author = {Schmidt, R. and Walz, Bernd}, title = {Serotonin and histamine produce different spatiotemporal Ca2+ signals in blowfly salivary glands}, issn = {0171-9335}, year = {2004}, language = {en} } @article{MargWalzBlenau2004, author = {Marg, S. and Walz, Bernd and Blenau, Wolfgang}, title = {The effects of dopamine receptor agonists and antagonists on the secretory rate of cockroach (Periplaneta americana) salivary glands}, issn = {0022-1910}, year = {2004}, abstract = {The acinar salivary glands of the cockroach, Periplaneta americana, are innervated by dopaminergic and serotonergic nerve fibers. Serotonin stimulates the secretion of protein-rich saliva, whereas dopamine causes the production of protein-free saliva. This suggests that dopamine acts selectively on ion-transporting peripheral cells within the acini and the duct cells, and that serotonin acts on the protein-producing central cells of the acini. We have investigated the pharmacology of the dopamine-induced secretory activity of the salivary gland of Periplaneta americana by testing several dopamine receptor agonists and antagonists. The effects of dopamine can be mimicked by the non-selective dopamine receptor agonist 6,7-ADTN and, less effectively, by the vertebrate D1 receptor-selective agonist chloro-APB. The vertebrate D1 receptor-selective agonist SKF 38393 and vertebrate D2 receptor-selective agonist R(-)- TNPA were ineffective. R(+)-Lisuride induces a secretory response with a slower onset and a lower maximal response compared with dopamine-induced secretion. However, lisuride-stimulated glands continue secreting saliva, even after lisuride-washout. Dopamine-induced secretions can be blocked by the vertebrate dopamine receptor antagonists cis(Z)- flupenthixol, chlorpromazine, and S(+)-butaclamol. Our pharmacological data do not unequivocally indicate whether the dopamine receptors on the Periplaneta salivary glands belong to the D1 or D2 subfamily of dopamine receptors, but we can confirm that the pharmacology of invertebrate dopamine receptors is remarkably different from that of their vertebrate counterparts. (C) 2004 Elsevier Ltd. All rights reserved}, language = {en} }