TY  - JOUR
A1  - Dames, Petra
A1  - Zimmermann, Bernhard
A1  - Schmidt, Ruth
A1  - Rein, Julia
A1  - Voss, Martin
A1  - Schewe, Bettina
A1  - Walz, Bernd
A1  - Baumann, Otto
T1  - cAMP regulates plasma membrane vacuolar-type H+-ATPase assembly and activity in blowfly salivary glands
N2  - Reversible assembly of the V0V1 holoenzyme from V-0 and V-1 subcomplexes is a widely used mechanism for regulation of vacuolar-type H+-ATPases (V-ATPases) in animal cells. in the blowfly (Calliphora vicina) salivary gland, V- ATPase is located in the apical membrane of the secretory cells and energizes the secretion of a KCl-rich saliva in response to the hormone serotonin. We have examined whether the CAMP pathway, known to be activated by serotonin, controls V-ATPase assembly and activity. Fluorescence measurements of pH changes at the luminal surface of isolated glands demonstrate that CAMP, Sp-adenosine-3',5'-cyclic monophosphorothioate, or forskolin, similar to serotonin, cause V-ATPase-dependent luminal acidification. In addition, V-ATPase-dependent ATP hydrolysis increases upon treatment with these agents. Immunofluorescence microscopy and pelleting assays have demonstrated further that V, components become translocated from the cytoplasm to the apical membrane and V-ATPase holoenzymes are assembled at the apical membrane during conditions that increase intracellular cAMP. Because these actions occur without a change in cytosolic Ca2+, our findings suggest that the cAMP pathway mediates the reversible assembly and activation of V-ATPase molecules at the apical membrane upon hormonal stimulus
Y1  - 2006
UR  - http://www.pnas.org/
U6  - https://doi.org/10.1073/pnas.0600011103
SN  - 0027-8424
ER  - 
TY  - JOUR
A1  - Zimmermann, Bernhard
A1  - Dames, Petra
A1  - Walz, Bernd
A1  - Baumann, Otto
T1  - Distribution and serotonin-induced activation of vacuolar-type H+-ATPase in the salivary glands of the blowfly Calliphora vicina
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Baumann, Otto
A1  - Dames, Petra
A1  - Kühnel, Dana
A1  - Walz, Bernd
T1  - Distribution of serotonergic and dopaminergic nerve fibers in the salivary gland complex of the cockroach Periplaneta americana
Y1  - 2002
UR  - http://www.biomedcentral.com/1472-6793/2/9
ER  - 
TY  - JOUR
A1  - Baumann, Otto
A1  - Kühnel, Dana
A1  - Dames, Petra
A1  - Walz, Bernd
T1  - Dopaminergic and serotonergic innervation of cockroach salivary glands : distribution and morphology of synapses and release sites
N2  - 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
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Dames, Petra
A1  - Schmidt, R.
A1  - Walz, Bernd
A1  - Baumann, Otto
T1  - Regulation of vacuolar-type H+-ATPase (vATPase) in blowfly salivary glands
Y1  - 2004
SN  - 0171-9335
ER  -