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A. A. Bukinich E. A. Tsvetkov N. P. Vesselkin 《Journal of Evolutionary Biochemistry and Physiology》2007,43(1):43-50
On isolated multipolar neurons of spinal cord of amniocoete (larva of the brook lamprey Lampetra planeri) by the patch-clamp method in configuration “the whole cell,” a modulating effect of dopamine on potential-activated Na+ currents was studied. Application of dopamine (10 μM) was shown to produce a complex action on the sodium current amplitude.
In some cases a decrease of the amplitude, on average, by 13.5 ± 2.2% was found, while in others—an increase, on average,
by 8.6 ± 6.1%. The modulation dopamine effect was not accompanied by any changes either of the threshold of the current appearance
or of resistance of neuronal cell membranes. Pharmacological analysis with use of dopamine agonist has shown that the agonist
of D1-receptors (−)-SKF-38393 (10 μM) decreases the Na+ current amplitude, whereas the agonist of D2-receptors (−)-quinpirole
(10 μM) can produce in different cells both an increase, by 30.7 ± 17.0%, and a decrease, by 13.2 ± 3.1%, of the Na+ current
amplitude. The obtained data indicate the existence of D1-and D2-receptors on the membrane of multipolar spinal neurons of
the amniocoete (larva of the brook lamprey). Study of action of antagonists has shown that the antagonist of D1-receptors
(+)-SCH-23390 (10 μM) does not affect action of the agonist of D1-receptors (−)-SKF-38393 (10 μM); the antagonist of D2-receptors
(−)-sulpiride (10 μM) blocks completely effects both of the agonist of D1-receptors (−)-SKF-38393 (10 μM) and of the agonist
of D2-receptors (−)-quinpirole (10 μM). The antagonist of D1-receptors (+)-SCH-23390 (10 μM) produced no effect on action
of the agonist of D1-receptors (−)-SKF-38393 (10 μM). The obtained data indicate peculiarities of dopamine receptors of Cyclostomata
as compared with those in mammals.
Original Russian Text ? A. A. Bukinich, E. A. Tsvetkov, and N. P. Vesselkin, 2007, published in Zhurnal Evolyutsionnoi Biokhimii
i Fiziologii, 2007, Vol. 43, No. 1, pp. 39–45. 相似文献
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G. G. Kurchavyi N. I. Kalinina N. P. Vesselkin 《Journal of Evolutionary Biochemistry and Physiology》2006,42(5):583-594
On preparations of the isolated spinal cord of the frog Rana ridibunda at intracellular recording from lumbar motoneurons, it is shown that response to the 10 mM GABA application decreased selectively
by 40.7 ± 23.7% (n = 6) as a result of the spinal cord treatment with bicuculline (100–150 μM), while response to the Gly application decreased
selectively by 50.7 ± 17.8% (n = 10) after the spinal cord treatment with strychnine (5–10 μM). Both strychnine and bicuculline produced potentiation of
EPSP by amplitude and duration as well as paroxysmal depolarizational shifts (PDS). Strychnine produced more effectively the
potentiation, while bicuculline—PDS. The inhibitory Gly effect decreased significantly the DR and RF EPSP (a decrease of amplitude
and duration) as a result of the spinal cord treatment with strychnine (5–10 μM), but not with bicuculline. The inhibitory
GABA effect on the DR and RF EPSP decreased as a result of the spinal cord treatment with bicuculline only in a half of the
studied motoneurons and to the lesser degree than the inhibitory Gly effect on the same EPSP at the strychnine treatment.
Based of the obtained data, it is suggested that the inhibitory effects on the excitatory inputs of the motoneuron in the
frog are expressed weaker than in mammals and are related predominantly to the GABA and Gly effects on receptors of interneurons.
It is suggested that GABA specifically acts mostly on GABAA receptors, whereas Gly—on Gly receptors, although there is some part of cross-inhibition.
Original Russian Text ? G. G. Kurchavyi, N. I. Kalinina, and N. P. Vesselkin, 2006, published in Zhurnal Evolyutsionnoi Biokhimii
i Fiziologii, 2006, Vol. 42, No. 5, pp. 463–471.
The present work is a continuation of the work [1]. 相似文献
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E. A. Tsvetkov I. S. Masalov N. P. Vesselkin 《Journal of Evolutionary Biochemistry and Physiology》2009,45(4):490-500
The work deals with study of role of inhibitory interneurons in the process of regulation of sensory currents converging on
soma of pyramidal cells of the dorsolateral amygdala nucleus as well as of role of these interneurons in mechanism of regulation
of plasticity of amygdala synapses. It has been shown that the part of the spontaneous inhibitory postsynaptic currents recorded
on the dorsolateral amygdala pyramidal cells is relatively high and amounts to about a half of the total amount of the recorded
events. Analysis of the evoked postsynaptic responses has shown the interneurons to regulate activity and duration of these
responses due to the postsynaptic membrane hyperpolarization as a result of activation of GABAA-receptors. Also studied was role of interneurons in providing mechanisms of the long-term potentiation of the synaptic responses
evoked by stimulation of cortical and thalamic inputs. Block of effect of interneurons with help of picrotoxin has been shown
to lead to an increase of evoked potentiation of synaptic responses. 相似文献
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G. G. Kurchavyi N. I. Kalinina N. P. Vesselkin 《Journal of Evolutionary Biochemistry and Physiology》2003,39(2):190-202
The effects of antagonists of excitatory amino acids (AP-5, kynurenate, and CNQX) on PSP recorded intracellularly in lumbar motoneurons of a preparation of the isolated spinal cord in the frog, Rana ridibunda, in response to activation of three different synaptic inputs (stimulation of DR, RF, and VC or LC) were analyzed. It is shown that the effects of the antagonists were non-uniform in different motoneurons. Inputs of suprasegmental and sensomotor projections substantially differed from each other. A considerable amount of DC-PSP resistant to kynurenate and CNQX was found, whereas the latter regularly inhibited DR-PSP in the same cell. The disynaptic, as judged by its latency, plane-shaped component was always relatively more stable to kynurenate as compared with other components. Unlike kynurenate that inhibited the early and late components, CNQF selectively depressed the early components of DR-PSP. 相似文献
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V. O. Adanina N. P. Vesselkin 《Journal of Evolutionary Biochemistry and Physiology》2017,53(5):423-426
Arborization of dorsal root afferents was studied in the lamprey spinal cord by the method of horseradish peroxidase transport. Direct evidence was obtained for the presence of efferent fibers in dorsal roots, representing collaterals that depart from ascending and descending intraspinal branches of sensory axons and travel towards the periphery through the adjacent roots. 相似文献
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S. V. Ovsepyan N. P. Vesselkin 《Journal of Evolutionary Biochemistry and Physiology》2002,38(6):743-754
The role of GABAA- and GABAB-receptors in presynaptic inhibition of primary afferent fibers was studied on an isolated preparation of the spinal cord of the frog Rana ridibunda. It is shown that the inhibitory effect of GABA on synaptic transmission from afferent fiber to motoneuron is caused by activation of both GABAA- and GABAB-receptors. A temporal correlation (± 5 min) was shown between the blocking action of bicuculline (a specific antagonist of GABAA-receptors) on primary afferent fiber depolarization (PAD) and its potentiating effect on the excitatory postsynaptic potential (EPSP) at parallel intracellular recording of EPSP in motoneuron and PAD in axons of the dorsal root. As a basis of this correlation, the single GABAA-receptor mechanism is discussed, which mediates the effect of bicuculline on PAD and EPSP. When a specific agonist of GABAB-receptor, baclofen, and an antagonist of GABAB-receptor, 2(OH)-saclofen, were applied, the obtained data indicated an involvement of GABAB-receptors in inhibition of synaptic transmission from afferent fibers to the motoneuron. Analysis of parameters of the unitary synaptic responses recorded in the control experiments and of their changes under the effect of (– )-baclofen indicates that the inhibitory action caused by activation of GABAB-receptors develops at the presynaptic level. 相似文献
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V. O. Adanina J. -P. Rio A. S. Adanina J. Reperan N. P. Vesselkin 《Cell and Tissue Biology》2008,2(5):486-492
The ultrastructure and immunospecificity of synapses on primary afferents and dorsal sensory cells (DCs) were studied in lamprey (Lampetra fluviatilis) spinal cords. Using the postembedding immunogold method with a combination of antibodies—polyclonal antibodies to glutamate and monoclonal antibodies to gamma-aminobutyric acid (GABA)—the presence of GABA-positive on the primary afferent axons and GABA-and glutamate-immunopositive synapses on the DC somatic membranes have been shown. Thus, it is obvious that sensory information in the lamprey is controlled by both presynaptic inhibition via synapses on the primary afferent axons and by direct synaptic influence on the body of the sensory neuron. 相似文献