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Barbara Stay - One of the best experts on this subject based on the ideXlab platform.
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effect of allatostatin and proctolin on antennal pulsatile organ and hindgut muscle in the cockroach diploptera punctata
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Angela B Lange, Kuen K Chan, Barbara StayAbstract:Diploptera punctata allatostatins are brain neuropeptides that inhibit juvenile hormone synthesis by corpora allata. They also occur in Nerves of many organs other than ocrpora allata. The distribution of allatostatins in, and the effect of allatostatins on two other organs, antennal pulsatile organ and hindgut, are demonstrated here. Allatostatin I-like immunoreactive material is present in cells of subesophageal and terminal abdominal ganglia; these ganglia are known to contain the cells that project to antennal Heart Nerve and proctodeal Nerve, respectively. Electron micrographs of both organs show Nerve terminals with allatostatic immunoreactive granules along with terminals containing nonimmunoreactive granules. Immunoreactive neurosecretory granules are about 200 nm in largest dimension. In the antennal pulsatile organ, profiles of the Nerve terminals are larger in the ampullar wall than in the muscle; in hindgut the terminals with immunoreactive granules are associated with the muscle net below the circular muscle. Hindgut responded to allatostatins I and IV with a dose-dependent decrease in amplitude and frequency of contraction that was reversible, with the threshold concentration for response between 10−8 and 10−7 M. In contrast, pulsatile organ muscle showed no such change with either allatostatin at 10−7–10−4 M. However, both organs responded to proctolin with increased amplitude and frequency of contractions. Allatostatins I and IV inhibited the proctolin-induced increase of hindgut contraction, whereas no such effect was seen in antennal pulsatile organ muscle. Extract of antennal pulsatile organ muscle showed proctolin-like bioactivity that comigrated with authentic proctolin on three sequential HPLC systems. © 1993 Wiley-Liss, Inc.
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allatostatins in the Nerves of the antennal pulsatile organ muscle of the cockroach diploptera punctata
Archives of Insect Biochemistry and Physiology, 1992Co-Authors: Andrea P. Woodhead, Carrie A Stoltzman, Barbara StayAbstract:The presence of allatostatins in the Nerves of the antennal pulsatile organ muscle of the cockroach Diploptera punctata was confirmed by immunocytochemistry, bioassay, and HPLC. Immunocytochemical reactivity with monoclonal antibody against allatostatin I showed strong allatostatin immunoreactivity in the antennal Heart Nerve which innervates this muscle with varicosities along the muscle fibers and in the insertion of the muscle on the pulsatile ampullae. Bioassay of Sep-Pak purified muscle extract demonstrated inhibition of juvenile hormone synthesis by corpora allata in vitro. A dose-response curve showed maximum inhibition of juvenile hormone synthesis was achieved with 10-20 pulsatile organ muscle eq/corpora allata, and 50% inhibition achieved with an estimated 2.6 pulsatile organ muscle eq. Two successive HPLC separations of the Sep-Pak purified extract yielded bioactive fractions corresponding to the elution times of the five known allatostatins.
M G Martynova - One of the best experts on this subject based on the ideXlab platform.
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atrial granular cells of the snail achatina fulica release proteins into hemolymph after stimulation of the Heart Nerve
The Journal of Experimental Biology, 2009Co-Authors: Sergej V Shabelnikov, O A Bystrova, Vadim Ivanov, Boris A Margulis, M G MartynovaAbstract:SUMMARY The atrium of the gastropod mollusc Achatina fulica receives rich innervation and contains numerous granular cells (GCs). We studied the atrial innervation and discovered that axon profiles typical in appearance of peptidergic neurons form close unspecialized membrane contacts with GCs. Then, we investigated, at both morphological and biochemical levels, the effect of electrical stimulation of the Heart Nerve on GCs of Achatina Heart perfused in situ. The ultrastructural study demonstrated changes in granule morphology consistent with secretion. These events included alteration of granule content, intracellular granule fusion and formation of complex degranulation channels, within which the granule matrix solubilized. It was shown that electrical stimulation resulted in a significant increase of the total protein concentration in the perfusate. Furthermore, SDS-PAGE analysis of the perfusate revealed three new proteins with molecular masses of 16, 22, and 57 kDa. Affinity-purified polyclonal antibodies against the 16 kDa protein were obtained; the whole-mount immunofluorescence technique revealed the presence of this protein in the granules of atrial GCs. In GCs of the stimulated atrium, a progressive loss of their granular content was observed. The results suggest that the central nervous system can modulate the secretory activity of the atrial GCs through non-synaptic pathways.
Sergej V Shabelnikov - One of the best experts on this subject based on the ideXlab platform.
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atrial granular cells of the snail achatina fulica release proteins into hemolymph after stimulation of the Heart Nerve
The Journal of Experimental Biology, 2009Co-Authors: Sergej V Shabelnikov, O A Bystrova, Vadim Ivanov, Boris A Margulis, M G MartynovaAbstract:SUMMARY The atrium of the gastropod mollusc Achatina fulica receives rich innervation and contains numerous granular cells (GCs). We studied the atrial innervation and discovered that axon profiles typical in appearance of peptidergic neurons form close unspecialized membrane contacts with GCs. Then, we investigated, at both morphological and biochemical levels, the effect of electrical stimulation of the Heart Nerve on GCs of Achatina Heart perfused in situ. The ultrastructural study demonstrated changes in granule morphology consistent with secretion. These events included alteration of granule content, intracellular granule fusion and formation of complex degranulation channels, within which the granule matrix solubilized. It was shown that electrical stimulation resulted in a significant increase of the total protein concentration in the perfusate. Furthermore, SDS-PAGE analysis of the perfusate revealed three new proteins with molecular masses of 16, 22, and 57 kDa. Affinity-purified polyclonal antibodies against the 16 kDa protein were obtained; the whole-mount immunofluorescence technique revealed the presence of this protein in the granules of atrial GCs. In GCs of the stimulated atrium, a progressive loss of their granular content was observed. The results suggest that the central nervous system can modulate the secretory activity of the atrial GCs through non-synaptic pathways.
O A Bystrova - One of the best experts on this subject based on the ideXlab platform.
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atrial granular cells of the snail achatina fulica release proteins into hemolymph after stimulation of the Heart Nerve
The Journal of Experimental Biology, 2009Co-Authors: Sergej V Shabelnikov, O A Bystrova, Vadim Ivanov, Boris A Margulis, M G MartynovaAbstract:SUMMARY The atrium of the gastropod mollusc Achatina fulica receives rich innervation and contains numerous granular cells (GCs). We studied the atrial innervation and discovered that axon profiles typical in appearance of peptidergic neurons form close unspecialized membrane contacts with GCs. Then, we investigated, at both morphological and biochemical levels, the effect of electrical stimulation of the Heart Nerve on GCs of Achatina Heart perfused in situ. The ultrastructural study demonstrated changes in granule morphology consistent with secretion. These events included alteration of granule content, intracellular granule fusion and formation of complex degranulation channels, within which the granule matrix solubilized. It was shown that electrical stimulation resulted in a significant increase of the total protein concentration in the perfusate. Furthermore, SDS-PAGE analysis of the perfusate revealed three new proteins with molecular masses of 16, 22, and 57 kDa. Affinity-purified polyclonal antibodies against the 16 kDa protein were obtained; the whole-mount immunofluorescence technique revealed the presence of this protein in the granules of atrial GCs. In GCs of the stimulated atrium, a progressive loss of their granular content was observed. The results suggest that the central nervous system can modulate the secretory activity of the atrial GCs through non-synaptic pathways.
Vadim Ivanov - One of the best experts on this subject based on the ideXlab platform.
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atrial granular cells of the snail achatina fulica release proteins into hemolymph after stimulation of the Heart Nerve
The Journal of Experimental Biology, 2009Co-Authors: Sergej V Shabelnikov, O A Bystrova, Vadim Ivanov, Boris A Margulis, M G MartynovaAbstract:SUMMARY The atrium of the gastropod mollusc Achatina fulica receives rich innervation and contains numerous granular cells (GCs). We studied the atrial innervation and discovered that axon profiles typical in appearance of peptidergic neurons form close unspecialized membrane contacts with GCs. Then, we investigated, at both morphological and biochemical levels, the effect of electrical stimulation of the Heart Nerve on GCs of Achatina Heart perfused in situ. The ultrastructural study demonstrated changes in granule morphology consistent with secretion. These events included alteration of granule content, intracellular granule fusion and formation of complex degranulation channels, within which the granule matrix solubilized. It was shown that electrical stimulation resulted in a significant increase of the total protein concentration in the perfusate. Furthermore, SDS-PAGE analysis of the perfusate revealed three new proteins with molecular masses of 16, 22, and 57 kDa. Affinity-purified polyclonal antibodies against the 16 kDa protein were obtained; the whole-mount immunofluorescence technique revealed the presence of this protein in the granules of atrial GCs. In GCs of the stimulated atrium, a progressive loss of their granular content was observed. The results suggest that the central nervous system can modulate the secretory activity of the atrial GCs through non-synaptic pathways.
