CCL

Összesen 5 találat.
#/oldal:
Részletezés:
Rendezés:

1.

001-es BibID:BIBFORM103137
035-os BibID:(WOS)000344348500008 (Scopus)84919882801
Első szerző:Röszer Tamás (orvos, biológus)
Cím:FMRF-amide is a glucose-lowering hormone in the snail Helix aspersa / Tamás Rőszer, Éva D. Kiss-Tóth
Dátum:2014
ISSN:0302-766X
Megjegyzések:Although glucose is metabolically the most important carbohydrate in almost all living organisms, still little is known about the evolution of the hormonal control of cellular glucose uptake. In this study, we identify Phe-Met-Arg-Phe-amide (FMRFa), also known as molluscan cardioexcitatory tetrapeptide, as a glucose-lowering hormone in the snail Helix aspersa. FMRFa belongs to an evolutionarily conserved neuropeptide family and is involved in the neuron-to-muscle signal transmission in the snail digestive system. This study shows that, beyond this function, FMRFa also has glucose-lowering activity. We found neuronal transcription of genes encoding FMRFa and its receptor and moreover the hemolymph FMRFa levels were peaking at metabolically active periods of the snails. In turn, hypometabolism of the dormant periods was associated with abolished FMRFa production. In the absence of FMRFa, the midintestinal gland ("hepatopancreas") cells were deficient in their glucose uptake, contributing to the development of glucose intolerance. Exogenous FMRFa restored the absorption of hemolymph glucose by the midintestinal gland cells and improved glucose tolerance in dormant snails. We show that FMRFa was released to the hemolymph in response to glucose challenge. FMRFa-containing nerve terminals reach the interstitial sinusoids between the chondroid cells in the artery walls. We propose that, in addition to the known sites of possible FMRFa secretion, these perivascular sinusoids serve as neurohemal organs and allow FMRFa release. This study suggests that in evolution, not only the insulin-like peptides have adopted the ability to increase cellular glucose uptake and can act as hypoglycemic hormones.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Glucose
Neuropeptide
Metabolism
Invertebrates
Hepatopancreas
Megjelenés:Cell And Tissue Research. - 358 : 2 (2014), p. 371-383. -
További szerzők:Kiss-Tóth Éva (1983-) (biológus)
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

2.

001-es BibID:BIBFORM012888
035-os BibID:(Wos)000284665200006 (Scopus)78649333360
Első szerző:Röszer Tamás (orvos, biológus)
Cím:Hypothermia translocates nitric oxide synthase from cytosol to membrane in snail neurons / Tamás Rőszer, Éva Kiss-Tóth, Dávid Rózsa, Tamás Józsa, A. József Szentmiklósi, Gáspár Bánfalvi
Dátum:2010
Megjegyzések:Neuronal nitric oxide (NO) levels are modulated through the control of catalytic activity of NO synthase (NOS). Although signals limiting excess NO synthesis are being extensively studied in the vertebrate nervous system, our knowledge is rather limited on the control of NOS in neurons of invertebrates. We have previously reported a transient inactivation of NOS in hibernating snails. In the present study, we aimed to understand the mechanism leading to blocked NO production during hypothermic periods of Helix pomatia. We have found that hypothermic challenge translocated NOS from the cytosol to the perinuclear endoplasmic reticulum, and that this cytosol to membrane trafficking was essential for inhibition of NO synthesis. Cold stress also downregulated NOS mRNA levels in snail neurons, although the amount of NOS protein remained unaffected in response to hypothermia. Our studies with cultured neurons and glia cells revealed that glia-neuron signaling may inhibit membrane binding and inactivation of NOS. We provide evidence that hypothermia keeps NO synthesis "hibernated" through subcellular redistribution of NOS.
Tárgyszavak:Orvostudományok Gyógyszerészeti tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
nitric oxide synthase
Megjelenés:Cell and Tissue Research. - 342 : 2 (2010), p. 191-203. -
További szerzők:Kiss-Tóth Éva (1983-) (biológus) Rózsa Dávid (1982-) (Ph.D hallgató) Józsa Tamás (1969-) (gyermeksebész, urológus) Szentmiklósi József András (1948-) (farmakológus, klinikai laboratóriumi szakorvos) Bánfalvi Gáspár (1943-) (sejtbiológus, gyógyszerész)
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

3.

001-es BibID:BIBFORM008293
035-os BibID:(Wos)000265622700014 (Scopus)67349249432
Első szerző:Röszer Tamás (orvos, biológus)
Cím:Acetylcholine inhibits nitric oxide (NO) synthesis in the gastropod nervous system / Tamás Rőszer, Tamás Józsa, A. József Szentmiklósi, Gáspár Bánfalvi
Dátum:2009
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Cell and Tissue Research. - 336 : 2 (2009), p. 325-335. -
További szerzők:Józsa Tamás (1969-) (gyermeksebész, urológus) Szentmiklósi József András (1948-) (farmakológus, klinikai laboratóriumi szakorvos) Bánfalvi Gáspár (1943-) (sejtbiológus, gyógyszerész)
Internet cím:elektronikus változat
DOI
Borító:

4.

001-es BibID:BIBFORM003340
035-os BibID:(Wos)000220863100011 (Scopus)2442660388
Első szerző:Röszer Tamás (orvos, biológus)
Cím:Nitric oxide synthesis is blocked in the enteral nervous system during dormant periods of the snail Helix lucorum L. / Tamás Rőszer, Zsolt Czimmerer, A. József Szentmiklósi, Gáspár Bánfalvi
Dátum:2004
ISSN:0302-766X
Megjegyzések:During dormancy of terrestrial snails, the whole neuromodulation of the nervous system is deeply modified. In this work we studied the adaptation of a previously described, putatively nitric oxide (NO) forming enteral network to the long-term resting periods of the snail Helix lucorum. The standard NADPH diaphorase (NADPHd) technique, which is an accepted method for histochemical NO synthase (NOS) detection, labeled the same enteric neurons of the midintestine in active or hibernated snails. Quantification of the NO-derived nitrite by the Griess reaction established that the nitrite formation is confined to the NADPHd-reactive network containing the midintestinal segment. In active snails, the nitrite formation could be enhanced by the NOS substrate l-arginine (10 mM?1 mM), but decreased by the known NOS inhibitors 1 mM Nw-nitro-l-arginine (NOARG) and 10 mM aminoguanidine (AG). Application of 1 mM larginine and 1 mM NOARG decreased the amplitude of the midintestinal muscle contractile activity, but did not affect the rectal motility. In dormancy, the nitrite formation was reduced in the NADPHd-reactive midintestinal network. Application of l-arginine could not provoke nitrite production and did not influence the midintestinal motility. Our findings indicate that NO is involved in the neural transmission to intestinal muscles of gastropods, but enteric release of NO is blocked during dormancy. The decreased NO synthesis is possibly due to an as yet undefined mechanism, by which the l-arginine/NO conversion ability of NOS could temporarily be inhibited in the long-term resting period of H. lucorum.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
NADPH diaphorase
nitric oxide synthase
hibernation
estivation
enteric nervous system
Helix lucorum L. (Mollusca)
Megjelenés:Cell and tissue research. - 316 (2004), p. 255-262. -
További szerzők:Czimmerer Zsolt (1981-) (molekuláris biológus) Szentmiklósi József András (1948-) (farmakológus, klinikai laboratóriumi szakorvos) Bánfalvi Gáspár (1943-) (sejtbiológus, gyógyszerész)
Internet cím:elektronikus változat
Borító:

5.

001-es BibID:BIBFORM001263
035-os BibID:(Wos)000239248000017 (Scopus)33746435763
Első szerző:Röszer Tamás (orvos, biológus)
Cím:Phe-met-arg-phe (FMRF)-amide is a substrate source of NO synthase in the gastropod nervous system / Tamás Rőszer, Éva Kiss-Tóth, Mihály Petkó, A. József Szentmiklósi, Gáspár Bánfalvi
Dátum:2006
Megjegyzések:The possible involvement of the L-arginine-containing Phe-met-arg-phe (FMRF)-amide (FMRFa) in neuronal nitric oxide (NO) biosynthesis was studied in a gastropod species. We found NADPH-diaphorase-positive neurons and FMRFa-containing fibers in close proximity in the enteric nervous system. Administration of L-arginine and FMRFa induced quantitatively similar nitrite production in both intact intestinal tissues and tissue homogenates. These changes could be prevented by the presence of NOARG (an NO synthase inhibitor). Neither chemically modified FMRFa (D-arginine instead of L-arginine) nor amino acid constituents of FMRFa (methionine, phenylalanine) affected basal nitrite production. FMRFa-induced alterations were reduced in the presence of Na+ channel blockers (tetrodotoxin, amiloride, lidocaine), the Na+/K+ATPase inhibitor ouabain, or protease inhibitors (leupeptine, pepstatine-a). FMRFa and its amino acid constituents were analyzed by paper chromatography. When FMRFa was added to tissue homogenates, the peptide was eliminated within 1-2 min, whereas methionine, phenylalanine, arginine, and citrulline levels were elevated simultaneously. We tested the effects of FMRFa, L-arginine, and NOARG on intestinal contractile activity. FMRFa relaxed the intestine for 1-2 min and then induced contractions for 20-40 min. In the presence of NOARG, no relaxant effect of FMRFa was recorded. As administration of L-arginine strongly inhibits the mechanical activity of the intestinal muscle, NO production presumably plays a substantial role in the action of FMRFa, at least in the initial phase. Our biochemical data indicate a direct involvement of FMRFa in NO biosynthesis. FMRFa might be hydrolyzed by extracellular peptidases and then the locally released arginine might be transported into the cells and broken-down to produce NO. Depolarization-induced NO production attributable to the activation of amiloride-sensitive Na+ channels might also be involved.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
neuropeptid NO szintáz szubsztrát
Megjelenés:Cell and Tissue Research. - 325 : 3 (2006), p. 567-575. -
További szerzők:Kiss-Tóth Éva (1983-) (biológus) Petkó Mihály (1943-) (orvos, neurobiológus) Szentmiklósi József András (1948-) (farmakológus, klinikai laboratóriumi szakorvos) Bánfalvi Gáspár (1943-) (sejtbiológus, gyógyszerész)
Internet cím:elektronikus változat
DOI
Borító:
Rekordok letöltése1 
Corvina könyvtári katalógus v8.2.27 © 2023 Monguz kft. Minden jog fenntartva.