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1.
Vestn Rentgenol Radiol ; (1): 22-6, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25864361

RESUMO

OBJECTIVE: To calculate Z scores for different age groups of women in the Kemerovo region, by relying on the developed database for two-dimensional bone mineral densities (BMD) of the lumbar vertebra and proximal femoral bone. MATERIAL AND METHODS: This given investigation analyzed 1504 results of dual-energy X-ray absorptiometry of the lumbar vertebra and proximal femoral bone in healthy women from the Kemerovo Region. RESULTS: The performed investigation revealed that the peak bone mass of the lumbar spine and proximal femoral bone in the Kuzbass women corresponded to that of 20-29-year olds. In the women of the Kemerovo Region, the population-based lumbar vertebral BMDs significantly differed from those available in the NHANES III database starting from 30 years of age. Thus, the developed BMD database has regional features and must be used to calculate a Z score for the female population of Kuzbass. By taking into account the fact that were no differences in the peak body mass values of the women in the two compared groups in accordance of the guidelines of the International Society for Clinical Densitometry; the NHANES III database may be used to estimate a T score.


Assuntos
Absorciometria de Fóton/métodos , Fêmur/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Osteoporose , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Reprodutibilidade dos Testes , Fatores de Risco , Sibéria/epidemiologia
2.
Artigo em Russo | MEDLINE | ID: mdl-25438580

RESUMO

The central pattern generator (CPG) is defined as a set of neurons involved in joint production of patterned motor output. The roundtable discussion on the CPG was a part of the 5th All-Russian Conference on Animal Behavior (Moscow, Nov. 21, 2012). The discussion centred on three core themes: 1) the mechanisms of the organization and reconfiguration of pattern generating neuronal ensembles, 2) extrapolations that extend the CPG concept beyond the motor systems, and 3) evolutionary and developmental aspects of CPG.


Assuntos
Geradores de Padrão Central/fisiologia , Animais , Evolução Biológica , Geradores de Padrão Central/crescimento & desenvolvimento , Humanos
3.
Angiol Sosud Khir ; 16(2): 50-3, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21032873

RESUMO

We surveyed a total of one hundred and ninety women presenting with small pelvic varicose veins (SPVIV). The chronic pelvic pain syndrome (CPPS) was revealed in nearly a quarter of the examined patients (24.7 %). The women's quality of life was assessed using the SF-36 questionnaire as a more integrative parameter, having demonstrated that women presenting with SPVV had a substantial decrease in all the components of both physical health and mental well-being. The obtained findings have strongly suggested the necessity of carrying out secondary prevention in women suffering from SPVV, even if there are no clinically pronounced manifestations of the disease.


Assuntos
Pelve Menor/irrigação sanguínea , Dor Pélvica/etiologia , Qualidade de Vida , Varizes , Interpretação Estatística de Dados , Emoções , Feminino , Nível de Saúde , Humanos , Saúde Mental , Dor Pélvica/psicologia , Prevenção Secundária , Inquéritos e Questionários , Síndrome
4.
Artigo em Inglês | MEDLINE | ID: mdl-18026734

RESUMO

Natural food odours elicit different behavioural responses in snails. The tentacle carries an olfactory organ, and it either protracts toward a stimulating carrot odour or retraces in a startle-like fashion away from a cucumber odour. The tentacle retraction to cucumber was still present after the snails were fed cucumber during inter-trial periods. Also, snails without any food experience displayed a longer latency to the first bite of cucumber than of carrot and rejected cucumber more often. After tasting these foods, the latency to carrot was not affected while the latency to and number of rejections of cucumber decreased. These results suggest that initial repulsive features of food odour can be only partially compensated by olfactory learning and feeding experience. In the present study, we demonstrated that an invertebrate can be repulsed or attracted by the same natural odour at the same time and that these behavioural responses are likely aimed at achieving different physiologically relevant goals.


Assuntos
Aprendizagem por Associação/fisiologia , Comportamento Alimentar/fisiologia , Caracois Helix/fisiologia , Reconhecimento Psicológico/fisiologia , Olfato/fisiologia , Animais , Aprendizagem da Esquiva/fisiologia , Condicionamento Clássico/fisiologia , Preferências Alimentares/fisiologia , Objetivos , Tempo de Reação/fisiologia , Receptores Odorantes/fisiologia , Órgãos dos Sentidos/fisiologia
5.
Neurosci Behav Physiol ; 36(3): 253-60, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16465488

RESUMO

The aims of the present work were to study the role of neuropeptide CNP4, encoded by the HCS2 gene (which is expressed mainly in parietal command interneurons), in controlling the activity of the respiratory system, and also to study the effects of this neuropeptide on isolated defensive behavior neurons in prolonged culture. The influence of the command interneuron on the pneumostoma included a direct effect consisting of closure and a delayed effect consisting of intensification of respiratory movements. Application of neuropeptide CNP4 produced a pattern similar to the delayed effects seen on stimulation of the command interneuron, i.e., significant increases in the frequency and intensity of pneumostoma movements and strengthening of the rhythmic activity of the pneumostoma motoneuron. Studies of the effects of neuropeptide CNP4 on isolated neurons after prolonged culture showed that neuron process growth correlated with the presence of the neuropeptide in the medium. Identification of the location of the HCS2 precursor protein and neuropeptide CNP4 in isolated command interneurons after prolonged culture showed that that only those parts of the cell showing active process growth were immunopositive. Thus, neuropeptide CNP4 appears to be a secreted neuropeptide controlling respiratory system activity, which may also be involved in rearrangements of the network controlling defensive behavior in Helix snails.


Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Gânglios dos Invertebrados/fisiologia , Caracois Helix/fisiologia , Interneurônios/fisiologia , Neurônios Motores/fisiologia , Neuropeptídeos/fisiologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Gânglios dos Invertebrados/citologia , Imuno-Histoquímica , Interneurônios/metabolismo , Neuropeptídeos/metabolismo , Respiração
6.
Neurosci Behav Physiol ; 36(1): 63-72, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16328171

RESUMO

The upper tentacle of the snail, bearing the olfactory organ, produces complex movements when the snail explores a new environment. Tentacle trajectories were reconstructed in the presence and absence of odors using two simultaneous video recordings. Reconstructions showed that in the absence of odor, snails constantly scanned the surrounding space with the extended tentacles. Presentation of an odor elicited rapid flexion, independent of the odor concentration, accompanied by concentration-dependent tentacle contractions. Activation of identified motoneuron MtC3 is known to elicit tentacle contraction. Recordings made in semi-intact preparations showed that the dynamics and duration of the spike activity of MtC3 produced in response to odors correlated with the degree of tentacle contraction in response to odors. These data suggest that the central motoneuron MtC3, which triggers tentacle contraction, is involved in controlling the margins of the scanning field. Slow contraction or extension of the tentacle, associated with the level of MtC3 activity, may operate to tune the snail's investigative behavior to the conditions of the sensory environment.


Assuntos
Movimento/fisiologia , Odorantes , Órgãos dos Sentidos/fisiologia , Olfato/fisiologia , Caramujos/fisiologia , Potenciais de Ação/fisiologia , Animais , Neurônios Motores/fisiologia , Órgãos dos Sentidos/citologia , Gravação em Vídeo
7.
Artigo em Russo | MEDLINE | ID: mdl-15828427

RESUMO

Helix Command Specific 2 (HCS2) gene is constantly expressed in parietal premotor (command) interneurons involved in control of the terrestrial snail Helix lucorum withdrawal behavior as a trigger element. It is also expressed under noxious conditions in other neurons presumably involved in withdrawal behavior. In this study we addressed the role of neuropeptide CNP4, encoded by gene HCS2, in the regulation of activity of the respiratory system, and in the influence on growth of isolated neurons in culture. It was shown that activity of the premotor interneuron elicits a direct effect (pneumostome closure), and a delayed intensification of respiratory movements. Application of CNP4 mimicked the delayed effects. Presence of the peptide CNP4 in solution for cultured neurons led to increase of neuronal growth. Immunochemical localization of the protein precursor encoded by gene HCS2 and peptide CNP4 in the cultured premotor interneurons revealed their preferential presence in the growth cones. The obtained results suggest that CNP4 may be secreted and involved in synergic regulation of behavior of a snail.


Assuntos
Comportamento Animal/fisiologia , Proteínas de Ligação ao Cálcio/genética , Neurônios Motores/fisiologia , Neuropeptídeos/genética , Neuropeptídeos/fisiologia , Animais , Expressão Gênica/genética , Caracois Helix , Respiração
8.
Artigo em Russo | MEDLINE | ID: mdl-15573703

RESUMO

The tentacle of terrestrial snail with olfactory organs on the tips display complex behavior when snail investigates the new environment. We reconstructed the trajectory of the tentacle in three dimensions from two simultaneous video recordings in freely moving snail without odor and after odor application. We found that without oder the snail displayed continuous environment scanning with elongated tentacles. Odor application elicited startle-like short-term flexions of the tentacle which were independent from odor concentration and concentration-dependent gradual tentacle contraction. Identified central motoneuron MtC3 is known to produce the most part of the central tentacle retraction to the noxious stimuli. In nose-brain preparation the MtC3 responded to odors in concentration-dependent manner similar by dynamics and duration to the concentration-dependent gradual tentacle contraction in intact snail. It suggests that the MtC3 provides the central control of the extent of the scanning area by limiting the tentacle length. The MtC3-related gradual contraction of the tentacle can be aimed to tune the olfactory behavior of the terrestrial snail to the particular odor environment.


Assuntos
Caracois Helix/fisiologia , Potenciais de Ação , Animais , Neurônios Motores/fisiologia , Olfato/fisiologia , Gravação em Vídeo
9.
Bull Exp Biol Med ; 132(1): 689-94, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11687855

RESUMO

Survival of neuronal ganglia from newborn snail (Helix aspera L.) in the brain of adult rats was studied. Snail ganglion survived in the brain of warm-blooded animals for 6 months without inducing immune conflict. At early stages (5 days) after transplantation, xenografts increased in size and were several times larger than native ganglia from 10-day-old snails, thereafter (on days 28 and 180) they became smaller still surpassing the sizes of ganglia from snail of the corresponding age. Rapid enlargement of the xenograft was due to cell reactive processes in the ganglion. Deep penetration of large vessels from xenografts to rat brain was observed.


Assuntos
Encéfalo/anatomia & histologia , Gânglios dos Invertebrados/transplante , Caracois Helix , Transplante Heterólogo , Animais , Encéfalo/citologia , Encéfalo/imunologia , Encéfalo/cirurgia , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/imunologia , Sobrevivência de Enxerto , Ratos , Ratos Wistar
10.
Exp Brain Res ; 141(3): 340-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11715078

RESUMO

GABA-immunoreactive fibers were observed in the neuropile of each ganglion of Helix lucorum, while GABA-immunoreactive neural somata were found only in the buccal, cerebral, and pedal ganglia. Bath application of 10(-5) M GABA to the preparation "buccal mass-buccal ganglia" elicited a sequence of radula movements characteristic of feeding behavior. Corresponding bursts of activity were recorded in the buccal nerves under GABA application and in the buccal neurons recorded optically. In preparations of isolated central nervous system, the bath applications of GABA (10(-5) to 10(-4) M) elicited no changes in synaptic input of the premotor interneurons involved in the withdrawal behavior. However, a significant decrease in amplitude of the synaptic input and in the number of spikes in responses elicited by the test nerve stimulation was observed in metacerebral serotonergic neurons involved in modulating the feeding behavior. GABA application inhibited the spontaneous spike activity in some pedal serotonergic neurons involved in the network underlying withdrawal responses and evoked bursting activity in the other neurons of this functional group. The effects of GABA application on mechanically isolated serotonergic neurons suggest that the primary effect of GABA is inhibition. Thus, our results give evidence of the putative role of GABA in activating the feeding behavior and in the synergistic suppression of serotonergic modulation of the withdrawal behavior and serotonergic modulation of feeding, which has corresponded to the observed behavioral suppression of withdrawal reactions during feeding.


Assuntos
Comportamento Animal/fisiologia , Caracois Helix/fisiologia , Ácido gama-Aminobutírico/fisiologia , Animais , Bochecha/inervação , Bochecha/fisiologia , Reação de Fuga/fisiologia , Comportamento Alimentar/fisiologia , Gânglios/citologia , Gânglios/fisiologia , Movimento/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo
11.
Brain Res ; 915(2): 125-32, 2001 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-11595201

RESUMO

It is known that a histocompatibility system is not developed to the same extent in lower invertebrates as in vertebrate animals. We assumed that the xenografts from the newborn invertebrate nervous system would not exert destructive effects on the brain of the vertebrate recipient even without immunosuppressive therapy. In search of brain xenografts (XG) capable to survive in the brain of a recipient without intensive immunosuppression, we transplanted ganglia of terrestrial snails into the rat brain. We compared effects of transplantation of the XG taken from anterior brain of the 18-day embryo chicken (XGC) and from ganglia of a newborn terrestrial pulmonate snail (Helix aspersa L., XGSn). Part of the XGSn were stained by vital fluorescent dyes Bisbenzimid or Fast Blue before grafting. The XGSn were implanted into the neocortex parenchyma in each hemisphere. Rat brains with the XGC were examined 5 days after, and brains with the XGSn - 5 and 28 days after the transplantation. Nonstained sections with the XGSn labeled with fluorescent dyes prior to transplantation were investigated in fluorescent microscope and stained later with tionin and cresyl-violet. Quantitative videoimage analysis of lymphocyte aggregations, reactive gliosis, morphology of the XG areas, and implantation trace was performed. It was found that the XGSn transplantation did not elicit in the rat brain an intensive immunological conflict 5 and 28 days after transplantation. In contrast, the XGC rapidly elicited a strong immune response resulting in massive obliterations in the rat brain and were rejected in 5 days. Labeled snail glia and vessels were observed in the stained XGSn 28 days after transplantation by fluorescence imaging. Putative snail vessels grew into the rat brain from the place of snail tissue transplantation serving the humoral integration of the XG and the host brain. Migration of molluscan glial cells was observed in the brain of recipients.


Assuntos
Encéfalo/patologia , Gânglios/imunologia , Transplante Heterólogo/patologia , Animais , Encéfalo/imunologia , Transplante de Tecido Encefálico/imunologia , Embrião de Galinha , Feminino , Gânglios/transplante , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Caracois Helix , Masculino , Ratos , Ratos Wistar , Transplante Heterólogo/métodos
12.
Neuroscience ; 103(2): 551-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11246168

RESUMO

A novel gene named Helix command-specific 2 (HCS2) was shown to be expressed predominantly in four giant parietal interneurons involved in withdrawal behavior of the terrestrial snail Helix lucorum L. and several single neurons in other ganglia. Decrease in spontaneous electrophysiological activity of neurons in the isolated CNS by 24h incubation in saline with elevated Mg(2+) concentration significantly decreased the number of HCS2-expressing neurons. Five short-term serotonin applications (each of 10microM), during a 24h incubation of the nervous system in saline induced expression of the HCS2 gene in many cells in cerebral, parietal, pleural and pedal ganglia. Dopamine applications under similar conditions were not effective. Application of anisomycin or cycloheximide, known to block protein synthesis, did not prevent the induction of HCS2 expression under serotonin influence. Skin injury elicited a significant increase in the number of HCS2-expressing cells 24h later in pleural and cerebral ganglia. Incubation of the isolated nervous system preparations for three days in culture medium elicited close to a maximum increase in number of HCS2-expressing cells. Elevation of the normal Mg(2+) concentration in the culture medium significantly decreased the number of cells demonstrating HCS2 expression. Application of the cAMP activator forskolin (10microM) increased the expression under Mg(2+), indicating that cAMP was involved in the up-regulation of HCS2. Application of thapsigargin (10microM), known to release Ca(2+) from intracellular stores, was also effective in increasing expression, suggesting participation of Ca(2+) in regulation of HCS2 expression. Cellular groups expressing the HCS2 gene under different conditions seem to be functionally related since it was demonstrated earlier that some neurons constituting these clusters are involved in the withdrawal behavior and the response of the organism to stress stimuli. From these results we suggest that the HCS2 pattern of expression can be down-regulated by a decrease in synaptic activity in the nervous system, and up-regulated by external noxious inputs, as well as the application of neurotransmitters and second messengers known to be involved in the withdrawal behavior and maintenance of isolated ganglia in culture medium. When up-regulated, the HCS2 expression appears, at least in part in neurons, to be involved in the withdrawal behavior.


Assuntos
Proteínas de Ligação ao Cálcio , Regulação da Expressão Gênica/fisiologia , Interneurônios/fisiologia , Neuropeptídeos/genética , Animais , Comportamento Animal/fisiologia , Temperatura Corporal , Colforsina/farmacologia , Dopamina/farmacologia , Eletrofisiologia , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Caracois Helix , Hibridização In Situ , Magnésio/farmacologia , Neurônios Aferentes/fisiologia , RNA Mensageiro/análise , Serotonina/farmacologia , Pele/lesões , Pele/inervação , Estresse Fisiológico/fisiopatologia , Cauda/lesões , Cauda/inervação
13.
Neurobiol Learn Mem ; 75(1): 30-50, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11124045

RESUMO

A cluster of 40 serotonergic cells in the rostral part of pedal ganglia of the terrestrial snail Helix lucorum was shown previously to participate in the modulation of withdrawal behavior and to be necessary during the acquisition of aversive withdrawal conditioning in intact snails. Local extracellular stimulation of the serotonergic cells paired with a test stimulus elicited a pairing-specific increase (the difference between paired and explicitly unpaired sessions was significant, p <.01) of synaptic responses to test stimulation in the premotor interneurons involved in withdrawal. This result suggested participation of serotonergic cells in mediating the reinforcement in the withdrawal network. Intracellular stimulation of only one identified Pd4 cell from the pedal group of serotonergic neurons paired with a test stimulus also significantly increased (the difference between paired and explicitly unpaired sessions was significant, p <.05) synaptic responses to paired nerve stimulation in same premotor interneurons involved in withdrawal. Morphological investigation of a cluster of pedal serotonergic neurons showed that only the Pd4 cell had branches in the parietal ganglia neuropile where the synapses of premotor withdrawal interneurons and of presynaptic neurons are located. The data suggest that a single serotonergic cell can mediate the reinforcement in the withdrawal network of the terrestrial snail. Patterns of responses of the Pd4 cells to tactile and chemical stimuli conform to the suggestion.


Assuntos
Comportamento Animal/fisiologia , Gânglios/citologia , Interneurônios/fisiologia , Rede Nervosa/fisiologia , Receptores de Serotonina/fisiologia , Reforço Psicológico , Animais , Axônios/fisiologia , Condicionamento Psicológico/fisiologia , Caracois Helix , Fatores de Tempo
14.
Artigo em Russo | MEDLINE | ID: mdl-10750195

RESUMO

It was shown earlier that some neurons in Helix CNS express the mRNA of the precursor of neuropeptide GFAD. Using the data obtained with the help of the whole-mount in situ hybridization, we tried to identify a group of such neurons, namely, the pedal caudo-ventral group and to determine their possible functions. The local extracellular stimulation of the pedal caudo-ventral group resulted in movements of reproductive organs in the semi-intact preparation and suppressed the activity of the modulatory neurons controlling feeding and defensive behavior. Application of synthetic peptide GFAD (10(-8) mol/l) also activated movements of the reproductive organs and suppressed the activity of the modulatory neuron controlling feeding behavior. Stimulation of the labial nerves resulted in suppression of caudo-ventral neurons with simultaneous activation of the modulatory neuron controlling feeding behavior. The obtained evidence suggests that the caudo-ventral neurons can regulate movements of the reproductive organs and also coordinate different functions in realization of the integral sexual behavior. This group of neurons inhibits the modulatory neurons controlling the forms of behavior incompatible with courtship, i.e., feeding and defensive forms.


Assuntos
Comportamento Animal/fisiologia , Caracois Helix/fisiologia , Neurônios/fisiologia , Neuropeptídeos/biossíntese , Animais , Comportamento Animal/efeitos dos fármacos , Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos , Gânglios dos Invertebrados/efeitos dos fármacos , Gânglios dos Invertebrados/fisiologia , Caracois Helix/efeitos dos fármacos , Técnicas In Vitro , Microeletrodos , Neurônios/efeitos dos fármacos , Neuropeptídeos/farmacologia , Processamento de Sinais Assistido por Computador
15.
Neuroscience ; 85(2): 637-47, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9622259

RESUMO

Nine giant interneurons located in the pleural and parietal ganglia of the terrestrial snail Helix lucorum L. were reported to be a key element in the network controlling withdrawal behaviour of the animal. Using a combination of complementary DNA subtraction cloning and differential screening approaches we have isolated a novel gene named HCS2 which is expressed predominantly in a subset of these interneurons. The predicted amino acid sequence of the HCS2 protein contains at the N-terminus a hydrophobic leader sequence and four putative neuropeptides, and at the C-terminus a perfect match to the consensus motif of the EF-hand family of the Ca2+-binding proteins. All four predicted neuropeptides bear a C-terminal signature sequence Tyr-Pro-Arg-X (where X is Ile, Leu, Val or Pro), and three of them are likely to be amidated. Physiological action of three synthetic peptides corresponding to the predicted mature HCS2 peptides mimics fairly well the described action of parietal interneurons on follower motoneurons controlling pneumostome closure. In situ hybridization experiments demonstrated that the HCS2 gene is selectively expressed in the four parietal giant interneurons, as well as in several small unidentified neurons. The onset of the HCS2 transcription during embryogenesis coincides temporally with the time-point when the first withdrawal responses of the embryo to tactile stimulation appear. We propose that the HCS2 gene encodes a hybrid precursor protein whose processed products act as neuromodulators or neurotransmitters mediating the withdrawal reactions of the snail, and in addition may participate in the calcium regulatory pathways or calcium homeostasis in command neurons.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Regulação da Expressão Gênica , Interneurônios/metabolismo , Neuropeptídeos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/fisiologia , Clonagem Molecular , Regulação da Expressão Gênica/fisiologia , Caracois Helix , Humanos , Interneurônios/química , Interneurônios/fisiologia , Dados de Sequência Molecular , Atividade Motora/fisiologia , Neuropeptídeos/química , Neuropeptídeos/fisiologia , Ratos , Análise de Sequência de DNA
16.
J Neurobiol ; 35(3): 271-6, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9622010

RESUMO

Neuronogenesis during posthatching development of the procerebrum of the terrestrial snail Helix lucorum was analyzed using bromodeoxyuridine immunohistochemistry to label proliferating cells. Comparison of the distribution of labeled cells in a series of animals which differed in age at the time of incubation with bromodeoxyuridine, in survival time after incubation, and in age at sacrifice reveals a clear pattern and developmental sequence in neuron origin. First, the proliferating cells are located only at the apical portion of the procerebrum. Second, cells which are produced at any particular age remain, for the most part, confined to a single layer in the procerebrum. Third, as development proceeds, each layer of previously produced neurons is displaced toward the basal part of the procerebrum by the production of additional neurons. Our results suggest that the vast majority of the neurons (probably about 70-80%) of the snail procerebrum are produced during the first 1-2 months of posthatching development.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Encéfalo/crescimento & desenvolvimento , Caracois Helix/crescimento & desenvolvimento , Neurônios/citologia , Animais , Bromodesoxiuridina , Divisão Celular/fisiologia , Imuno-Histoquímica
17.
J Neurobiol ; 35(2): 183-97, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9581973

RESUMO

We report the isolation of a cDNA clone encoding a neuropeptide precursor named preproGFAD from the central nervous system (CNS) of the snail Helix lucorum. Analysis of the expression of this gene shows that it is neurospecific and expressed in several groups of CNS neurons. Most notable is the expression of preproGFAD gene in the right mesocerebrum, where the neurons controlling mating behavior are located. The expression in this particular region is observed in adult animals but not in juvenile ones. The preprohormone is 108 amino acids long and contains a hydrophobic leader peptide and eight Lys-Arg recognition sites for endoproteolysis. The post-translational processing of the prohormone may lead to the generation of seven tetrapeptides, Gly-Phe-Ala-Asp-COOH (GFAD). This peptide has the same sequence as two previously isolated peptides from a related snail, Achatina fulica. The first of them (achatin-I) contains D-Phe; the second (achatin-II) is its L-Phe-containing stereoisomer. Injection of synthetic D-GFAD in nanomolar concentrations into intact animals caused an increase of the heartbeat rate and opening of the genital atrium. In preparations containing CNS with intact innervation of reproductive organs, bath application of D-GFAD caused extensive movements of the penis but not of other reproductive organs. Intracellular activation of individual neurons expressing the preproGFAD gene also elicited penis movements. D-GFAD also suppressed activity of neurons modulating feeding behavior. Our data therefore indicate that the preproGFAD gene encodes the precursor of a neuropeptide that participates in the regulation of male mating behavior.


Assuntos
Sistema Nervoso Central/metabolismo , Regulação da Expressão Gênica/fisiologia , Neurônios/metabolismo , Neuropeptídeos/genética , Precursores de Proteínas/genética , Comportamento Sexual Animal/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Caracois Helix , Masculino , Dados de Sequência Molecular
18.
Artigo em Russo | MEDLINE | ID: mdl-9273796

RESUMO

The distribution of serotonin- (5-HT) and dopamine- (DA) containing neurons was studied in the brain of adult and juvenile (the first month of life) terrestrial molluscs Helix lucorum and Eobania vermiculata by means of glyoxylic acid fluorescent technique and neurotoxin 5,7-DiHT labelling. The majority of 5-HT-containing cells were grouped in clusters in the pedal ganglia (the median number of cells in a cluster was 213 in Eobania and 155 in Helix). Some cells were described in the cerebral ganglia, visceral and right parietal ganglia. DA-containing neurons were found in the buccal ganglia, cerebral ganglia (there were 6-8 large dorsal cells and about 80 small ventral cells) and pedal ganglia (the median number of cells was 36 in Helix and 12 in Eobania). In juvenile animals of both species the number and distribution of clusters with monoaminergic cells resembled that of the adults. In the juvenile pedal ganglia the number of 5-HT-containing cells was about one fourth of that in adult snails. The number of DA-containing cells in juveniles was the same as in adults in both species. In juvenile snails of both species one big and two medium-sized 5-HT-containing cells were found at the dorsal surface of the cerebral ganglia. Such cells were not revealed in adults. The finding suggests that these cells can change the transmitter phenotype or be transient.


Assuntos
Caracois Helix/fisiologia , Neurônios/fisiologia , Receptores Dopaminérgicos/fisiologia , Receptores de Serotonina/fisiologia , Caramujos/fisiologia , 5,7-Di-Hidroxitriptamina/farmacologia , Animais , Caracois Helix/efeitos dos fármacos , Histocitoquímica , Neurônios/efeitos dos fármacos , Neurotoxinas/farmacologia , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Agonistas do Receptor de Serotonina/farmacologia , Caramujos/efeitos dos fármacos
19.
Neuroreport ; 8(16): 3631-5, 1997 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-9427339

RESUMO

We report the isolation of a Helix lucorum cDNA clone encoding a precursor of neuropeptides that are closely related to Aplysia and Tritonia pedal peptides (Pep). The predicted propeptide contains 20 copies of the two variants of Helix Pep interspersed with Lys-Arg endopeptidase cleavage sites. Northern blot hybridization revealed multiple Pep-hybridizing species in the Helix CNS RNA. The Pep gene was expressed by several identified serotonergic neurones in pedal and cerebral ganglia, groups of sensory neurones in procerebrum, peripheral neurones in olfactory bulb, mantle and foot, and group of neurones in pedal ganglia presumably involved in locomotion control. Pep mRNA was detected in several neurones at the early stages of nervous system development.


Assuntos
Gânglios dos Invertebrados/metabolismo , Caracois Helix/metabolismo , Neuropeptídeos/biossíntese , Sequência de Aminoácidos , Animais , Aplysia/metabolismo , Clonagem Molecular , DNA Complementar , Dados de Sequência Molecular , Neurônios/metabolismo , Neuropeptídeos/química , Precursores de Proteínas/biossíntese , Precursores de Proteínas/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
20.
Invert Neurosci ; 2(1): 61-9, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9372156

RESUMO

A search for genes specifically expressed in the giant interneurons of parietal ganglia of the snail Helix lucorum yielded, among others, two genes named HDS1 and HDS2. According to data obtained by Northern hybridization and whole-mount in situ hybridization, both genes are neurospecific and expressed almost exclusively in the peptidergic D-group neurons (Sakharov, 1974) located in the right parietal ganglion. In situ hybridization of the HDS1 and HDS2 probes with CNS of several related species of the Helicoidea superfamily identified in all cases similarly located homologous groups of neurons. Sequencing of the near full-length cDNA copies of the HDS1 and HDS2 genes revealed open reading frames 107 and 102 amino acids long for HDS1 and HDS2, respectively. Both putative proteins contain a hydrophobic leader peptide and putative recognition sites for furin-like and PC-like endopeptidases. Predicted amino acid sequences of the HDS1 and HDS2 proteins were found to be moderately homologous to each other, as well as to the LYCP preprohormone expressed by the light yellow cells of the freshwater snail Lymnaea stagnalis. These results confirm an earlier hypothesis that the D-group of the Helix family and the light yellow cells of Lymnaea stagnalis represent homologous neuronal groups. Our data suggest that the HDS1 and HDS2 genes encode precursors of secreted molecules, most likely neuropeptides or neurohormones.


Assuntos
Gânglios dos Invertebrados/fisiologia , Caracois Helix/genética , Interneurônios/fisiologia , Proteínas do Tecido Nervoso/genética , Neuropeptídeos , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , DNA Complementar/genética , Gânglios dos Invertebrados/citologia , Dosagem de Genes , Hibridização In Situ , Dados de Sequência Molecular
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