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Purpose:There is considerable concern about potential effects associated with exposure to magnetic fields on organisms. Therefore, duration of pupa-adult development and motor behaviour of adults were analyzed in Tenebrio obscursus and T. molitor after exposure to static magnetic field (50 mT). Material and methods:The experimental groups were:Control (kept 5 m from the magnets), groups which pupae and adults were placed closer to the North pole, or closer to the South pole of magnetic dipole. The pupae were exposed to the magnetic field until the moment of adult eclosion. The pupa-adult development dynamics were recorded daily. Subsequently, behaviour (distance travelled, average speed and immobility) of adults exposed to the magnetic field was monitored in a circular open field arena. Results:Static magnetic field did not affect pupa-adult developmental dynamic of examined Tenebrio species. Exposure to magnetic field did not significantly change motor behaviour of T. obscurus adults. The changes in the motor behaviour of T. molitor induced by static magnetic field were opposite in two experimental groups developed closer to the North pole or closer to the South pole of magnetic dipole. Conclusion:Static magnetic field (50 mT) did not affect on pupa-adult development dynamic of two examined Tenebrio species, but modulated their motor behaviour.

Purpose. To examine the effects of acute exposure to strong static magnetic fields and extremely low frequency magnetic fields, on neurosecretory neurons which synthesise insulin-like neurohormone. Materials and methods: Immunocytochemical detection of bombyxin-like material in the protocerebral neurosecretory neurons of Lymantria dispar caterpillars was performed using a monoclonal antibody directed against a synthetic dekapeptide corresponding to the N-terminus of the bombyxin A-chain. Caterpillars were exposed to strong static magnetic fileds (235 mT) and extremely low frequency magnetic fields (2 mT) for three days after moulting into the 4th instar. Results: We report the presence of immunoreactive molecules in A2 type of medial neurosecretory neurons (nsn) in caterpillars' brain of L. dispar. The three-day exposure of caterpillars to stresogenic external magnetic fields changed the size of A2 type nsn, their nuclei and the intensity of protein band in the region of bombyxin molecular mass (4-6 kD) after exposure to extremely low frequency magnetic fields in comparison to control group and group treated by strong static magnetic fields. Conclusion: These are the first data on the influence of external magnetic fields on the polyphagous phytophagous forest pest L. dispar L. (Lepidoptera: Lymantridae) indicating an intensive synthesis of insulin-like neurosecretory material. Serbian Ministry of Science and Technological Development [173027]

Purpose: The morphometric characteristics of A1 and A2 protocerebral neurosecretory neurons (cell and nuclei size, number of nucleoli in the nuclei); corpora allata size, nuclei size, cell number, were investigated in the pupae of yellow mealworm, Tenebrio molitor (L.), exposed to a strong static magnetic field of 320 mT maximum induction (10,000 times higher than the Earth's). Materials and methods: The experimental groups of Tenebrio molitor pupae were: A control group exposed only to natural magnetic field and sacrificed at the eighth day of pupal development (C); and pupae kept in a strong static magnetic field for eight days and then sacrificed (MF). Serial brain cross-sections were stained using the Alcian Blue Floxin technique. All the parameters were analyzed and measurements were performed using an image processing and analysis system (Leica, Cambridge, UK) linked to a Leica DMLB light microscope (program is QWin - Leica's Quantimet Windows-based image analysis tool kit). Results: The values of morphometric parameters of neurosecretory neurons and corpora allata were significantly increased after exposure of the pupae to the strong magnetic field. Conclusions: The strong magnetic field influence characteristics of protocerebral neurosecretory neurons and corpora allata in the late Tenebrio molitor pupae. null

The activity of large dorsomedial protocerebral A2' neurosecretory neurons were investigated in late pupae of Tenebrio molitor L, which were exposed to a static magnetic field of 320mT. Experimental groups were C: the control group which was kept at 5 meters from the magnet; CMF: pupae which were reared in control conditions and sacrificed on the eighth day of pupal stage (parents were kept in a magnetic field); and MF: pupae kept in a permanent magnetic field for eight days. Our results indicate the effects of a static magnetic field on the cytological characteristics and activity of large A2' neurosecretory neurons of Tenebrio molitor pupae. null

The effects of different temperatures (23°C and 8°C) on activity of corpora allata (CA) and dorsolateral (L1, L2) protocerebral neurosecretory neurons were investigated in Morimus funereus Mulsant (1863) larvae collected from a natural population during March. Activity of CA was revealed by monitoring of CA volume and cell number. Increase of CA volume after two day exposure to both temperatures was shown to be the result of increase in cell number. Activity of CA was higher at 23°C than 8°C. Activity of L1 and L2 neurosecretory neurons was inhibited at both temperatures. Neurosecretory neurons were more sensitive to temperature of 23°C than 8°C. It can be supposed that dorsolateral neurosecretory neurons synthesize neurohormones that affect CA activity, depending on environmental temperature. Ispitivan je uticaj različitih temperatura (23°C i 8°C) na aktivnost corpora allata (CA) i dorzolateralnih (L1 i L2) protocerebralnih neurosekretnih neurona kod larvi Morimus funereus Muls. (1863), sakupljenih iz prirode tokom meseca marta. Aktivnost CA je procenjivana praćenjem promena veličine CA i broja ćelija CA. Pokazano je da je povećanje veličine CA, nakon 2 dana izlaganja larvi obema temperaturama, rezultuje u povećanju broja ćelija. Aktivnost CA je veća na temperaturi od 230C, nego na 80C. Aktivnost L1 i L2 neurosekretnih neurona je bila inhibirana delovanjem obeju temperatura. Neurosekretni neuroni su osetljiviji na delovanje temperature od 230C, nego na 80C. Moglo bi se pretpostaviti da dorzolateralni neurosekretni neuroni sintetišu neurohormone koji utiču na aktivnost CA, u zavisnosti od temperature spoljašnje sredine. Projekat ministarstva br. 1615

The development of new technologies in the last decades has actuated researches on effects of magnetic and electromagnetic fields on individual performance and physiological reactions in living systems. Our work is based on the model of pupal development and compares insect species belonging to different orders: Tenebrio molitor (Coleoptera), Drosophila melanogaster (Diptera) and Apis mellifera (Hymenoptera). A highly significant increase in the rate of adult eclosion was detected in all examined species reared under constant external magnetic field suggesting unique mechanisms of magnetic field influence on development of three evolutionary distant insect species. Razvoj novih tehnologija poslednjih decenija je pokrenuo istraživanja efekata magnetnih i elektromagnetnih polja na individualnu performansu i fiziološke reakcije u živim sistemima. Naš rad je baziran na modelu lutkinog razvića i poredi tri evolutivno udaljene vrste insekata koje pripadaju različitim redovima: Tenebrio molitor (Coleoptera), Drosophila melanogaster (Diptera) i Apis mellifera (Hymenoptera). Kod svih proučavanih vrsta je uočen statistički značajan porast brzine izleganja adulta pod uticajem spoljašnjeg magnetnog polja što ukazuje na jedinstvene mehanizme delovanja na procese razviće kod tri udaljene vrste insekata. null

Spoljašnja magnetna polja (MP) narušavaju ravnotežu bioloških sistema, čak i tokom kraćeg vremena izlaganja, što za posledicu ima poremećaje na različitim nivoima organizacije. Na ovaj način nastali poremaćaji akumuliraju se u organizmima, što je jedan od razloga za traženje objašnjenja bioloških efekata MP. S druge strane, veoma važna činjenica koja nas usmerava na što bolje razumevanje ove problematike je potreba za zaštitom ljudskog zdravlja zbog uvođenja novih tehnologija u svakodnevni život, industriju i medicinu, kao i zbog terapijske upotrebe MP. Pretpostavka je da se interakcija spoljašnjih MP i organizama dešava na svim nivoima organizacije, uključujući i nervni sistem. Stoga je cilj ovih istraživanja bio ispitivanje uticaja elektromagnetnog polja (2 mT, 50 Hz) različitih karakteristika (trajanje, talasni oblik) na spontanu bioelektričnu aktivnost neurona antenalnog lobusa adulta Morimus funereus. Aktivnost neurona (pozadinskih/neuronske populacije i najbližih registrujućoj elektrodi) je registrovana kroz nekoliko faza u kojima smo adulte izlagali sinusoidalnom ili kvadratnom MP različitog trajanja: 5, 10 i 15 min (MP-5, MP-10, MP-15, respektivno). Uticaj MP smo procenjivali na osnovu promena u neuronskoj aktivnosti, a procenjivali smo i (i)reverzibilnost promena između tripleta formiranih od određenih eksperimentalnih faza. U tripletima koji slede vremenski tok eksperimenta, a podrazumevaju delovanje MP određenog trajanja (MP-5, MP-10 i MP-15, respektivno), testirali smo i njihove međusobne razlike. Rezultati istraživanja su pokazali da primenjeno MP, bez obzira na dužinu izlaganja i talasni oblik, menja aktivnost neurona antenalnog lobusa. U sinusoidalnom MP, te promene su najizraženije nakon delovanja MP-15, a u kvadratnom MP, nakon delovanja MP-5. Pokazano je da je kontrolna aktivnosti pozadinskih neurona značajno promenjene nakon delovanja sinusoidalnog MP-5, kao i nakon delovanja MP-10, a značajno je manja nakon delovanja MP-15. S druge strane, sinusoidalno MP, bez obzira na dužinu izlaganja izaziva značajnu inhibiciju kontrolne aktivnosti najbližih neurona. Promene kontrolne neuronske aktivnosti su značajno manje nakon delovanja kvadratnog MP različitog trajanja (i MP-5 i MP-10 i MP-15). U odnosu na aktivnost neposredno nakon izlaganja sinusoidalnom MP, povećanje neuronske aktivnosti 35 min nakon izlaganja je za pozadinske neurone značajno u MP-5, a za najbliže neurone u MP-10. Promene neuronske aktivnosti 35 min po prestanku izlaganja kvadratnom MP-5 u odnosu na aktivnost neposredno nakon izlaganja su značajne i kod pozadinskih i kod najbližih neurona. S druge strane, neuronska aktivnost 35 min po prestanku izlaganja kvadratnom MP-10 je kod pozadinskih neurona bila značajno veća, a kod najbližih neurona značajno manja u odnosu na aktivnost neposredno nakon izlaganja. Promene neuronske aktivnosti koje nastaju usled izlaganja sinusoidalnom/kvadratnom MP različitog trajanja, u većini slučajeva su imale ireverzibilan karakter. Sinusoidalno MP različitog trajanja ne izaziva značajne promene faktora reverzibilnosti između tripleta eksperimentalnih faza koji podrazumevaju delovanje MP određenog trajanja. Nasuprot tome, kvadratno MP značajne razlike izaziva kod najbližih neurona i to između tripleta koji uključuju delovanje MP-10 i MP-15. Na osnovu svega navedenog, možemo zaključiti da su jedinke M. funereus osetljive na delovanje i sinusoidalnog i kvadratnog elektromagnetnog polja (2 mT, 50 Hz) različitog trajanja i da njihova reakcija zavisi od karakteristika primenjenog polja, kao i od individualnih specifičnosti jedinki ove vrste. Takođe, naši rezultati ukazuju na činjenicu da M. funereus ima sposobnost da detektuje i odgovara na spoljašnja magnetna polja. External magnetic fields (MF) disturb the equilibrium of biological systems, even during short-term exposure, resulting in disturbances at different levels of organization. These changes accumulate in organisms, which is one of the reasons for testing biological effects of MF. On the other hand, the fact that modern man is exposed to increasing number of MF sources due to the use of new technologies in everyday life, industry, medicine, as well as therapeutic application of MF, makes this topic even more important, in terms of human health protection. It is assumed that the interaction between external MF and organisms takes place at all levels of organization, including the nervous system. Thus, the aim of this study was to investigate the influence of electromagnetic field (EMF) of different characteristics (exposure duration, waveform) on spontaneous bioelectrical activity of antennal lobe neurons of adult Morimus funereus. Neurons activity (background/neuronal population and those nearest to the recording electrode) was registered through several phases of exposure of adult longhorn beetles to sine wave or square wave MF of different exposure duration: 5, 10 and 15 minutes (MP-5, MP-10 and MP-15, respectively). Estimation of MF influence was based on registered changes of neuronal activity. (I)reversibility of such changes was tested through comparison the triplets formed by particular experimental phases. Changes in triplets that follow the time course of the experiment, with reference to MF influence of different exposure duration (MP-5, MP-10 and MP-15, respectively), were also tested. Results of this study showed that the applied MF, regardless of exposure duration and waveform, modifies the activity of antennal lobe neurons. In sine wave MF, the most prominent changes are recorded after MP-15, while in square wave MF such changes were recorded after MP-5. Control activity of the neuronal population was significantly changed both after MP-5 and MP-10, as well as significantly decreased after MP-15. Sine wave MF, regardless of exposure duration, significantly inhibits control activity of nearest neurons. Changes in control neuronal activity are significantly lower in square wave MF of different exposure duration (MP-5, MP-10, MP-15). Compared to the activity detected immediately after exposure to sine wave MF, the activity of neuronal population and nearest neurons is significantly increased 35 minutes after cessation of MF-5 and MP- 10 exposure, respectively. In case of square wave MF, changes in the activity of neuronal population and nearest neurons are significant 35 minutes after cessation of MF-5 exposure compared to the activity detected immediately after exposure to this MF. On the other hand, the neuronal activity detected 35 minutes after cessation of MF-10 exposure was significantly higher in the neuronal population and significantly lower in the nearest neurons compared to the activity detected immediately after exposure to this square wave MF. Changes in the activity of neurons exposed to sine wave or square wave MF of different duration were mostly irreversible. Sine wave MF of different duration does not change reversibility factors between the triplets formed by particular experimental phases. In contrast, in square wave MF, reversibility factors of the nearest neurons are significantly changed between the triplets formed by MP-10 and MP-15 experimental phase. Results of our experiment imply that M. funereus individuals are sensitive to both sine wave and square wave EMF (2 mT, 50 Hz) of different duration, whereby their reactions depend on the characteristics of the applied MF and specificity of each individual. In addition, it can be presumed that adult M. funereus has the ability to detect and respond to external MF.

U današnje vreme, jedna od najčešćih bolesti koja pogaña celokupno društvo je moždani udar, koji može biti uzrokovan moždanom ishemijom. Osim što u velikom procentu dovodi do smrti, posledice moždanog udara su najčešće trajne i za njih ne postoji efikasna terapija. Još jedna karakteristika modernog doba je razvitak elektronske industrije i primena sve raznovrsnijih električnih ureñaja, a samim tim i povećanje stepena zagañenja “elektromagnetnim smogom”. Povećano prisustvo niskofrekventnih elektromagnetnih polja (EMP) je privuklo interesovanje velikog broja naučnika te su ispitivani njegovi efekti, izmeñu ostalog i na funkcionalne karakteristike centralnog nervnog sistema. Na osnovu poznatih činjenica o njegovom dejstvu možemo pretpostaviti da ovo polje utiče i na razvoj patofizioloških dogañaja i oporavak u uslovima moždane ishemije. Cilj naše studije je bio da ispitamo da li elektromagnetno polje (0,5 mT, 50 Hz, u trajanju od 7 dana) utiče na hipermotorno ponašanje pustinjskih miševa izazvano 10-min globalnom moždanom ishemijom i to 1., 2., 4. i 7. dana (neposredan efekat EMP), kao i 14. dana nakon reperfuzije (odloženi efekat EMP). Takoñe, na modelu moždane ishemije smo ispitali da li primenjeno EMP utiče na parametre oksidativnog stresa, koji su inače povišeni nakon moždane ishemije, u pojedinim regionima mozga 7. i 14. dana nakon reperfuzije. Praćen je i uticaj EMP na morfološke promene u najosetljivijim strukturama mozga (hipokampus, striatum i kora velikog mozga) izazvane ishemijom 7. i 14. dana nakon reperfuzije i morfometrijskom analizom su kvantifikovane promene na neuronima i glijalnim ćelijama. Ponašanje eksperimentalnih životinja je registrovano u trajanju od 60 minuta u testu otvorenog polja - “open field”-u. Pokazano je da 10-min ishemija indukuje značajno povećanje motorne aktivnosti (lokomocija, stereotipija i rotacije) do 4. dana nakon reperfuzije. Izlaganje eksperimentalnih životinja EMP je inhibiralo razvitak hipermotorne aktivnosti izazvane ishemijom i to značajno u prva dva dana nakon reperfuzije kada je i postishemijska hiperaktivnost najuočljivija. Motorna aktivnost ovih pustinjskih miševa je bila značajno povećana u poreñenju sa kontrolnom grupom samo prvog dana nakon reperfuzije. Biohemijski su odreñeni parametri oksidativnog stresa (NO, O2-, SOD, ILP) u hipokampusu, striatumu i kori prednjeg mozga. Ishemija dovodi do povećanja oksidativnog stresa u svim ispitivanim strukturama mozga i to kako 7. tako i 14. dana nakon reperfuzije, a vrednosti za SOD ostaju na kontrolnom nivou. EMP takoñe povećava produkciju slobodnoradikalskih vrsta 7. dana (neposredni efekat EMP) ali u značajno većoj meri nego ishemija, kao i aktivnost SOD. Sedam dana nakon završetka izlaganja (odloženi efekat EMP) izmerene vrednosti parametara oksidativnog stresa su na nivou kontrolnih. Ishemični pustinjski miševi izloženi EMP imaju povećane vrednosti merenih parametara oksidativnog stresa 7. dana nakon reperfuzije (neposredni efekat EMP), ali u znatno manjoj meri nego jedinke ishemične grupe ili grupe izložene EMP. Parametri oksidativnog stresa u mozgu ishemičnih pustinjskih miševa izloženih EMP su na nivou kontrolnih 14. dana nakon reperfuzije. Primenom stereoloških metoda, utvrñeni su volumeni striatuma i hipokampusa, volumenska gustina oštećenih neurona i astrocita, kao i broj mikroglijalnih ćelija po jedinici površine u hipokampusu. Izlaganje EMP nije dovelo do morfoloških promena u ispitivanim strukturama, dok je 10-min globalna moždana ishemija dovela do ćelijske smrti u najvećoj meri u CA1 regionu hipokampusa. Ishemični pustinjski miševi izloženi EMP su imali znatno niži stepen propalih ćelija i veći odgovor astrocita i mikroglijalnih ćelija nego postishemijski pustinjski miševi bez izlaganja 7. dana nakon reperfuzije (neposredni efekat EMP). Sličan odgovor je zapažen i 14. dana nakon reperfuzije (odloženi efekat EMP). Rezultati ovih istraživanja su pokazali da primenjeno EMP (0,5 mT, 50 Hz) smanjuje motornu hiperaktivnost izazvanu 10-min globalnom moždanom ishemijom modulacijom procesa koji leže u osnovi ovakvog ponašanja. Takoñe, EMP smanjuje oksidativni stres izazvan globalnom moždanom ishemijom i na taj način smanjuje moguće negativne posledice koje slobodnoradikalske vrste imaju u mozgu. EMP pokazuje i neuroprotektivnu ulogu u hipokampusu, najosetljivijoj strukturi na ishemijsko oštećenje, redukujući broj oštećenih neurona i aktivirajući astrocite i mikroglijalne ćelije. Nowadays, one of the most common diseases, which affect the whole society, is brain stroke, which can be caused by cerebral ischemia. Beside high mortality rate, consequences of brain stroke are often permanent without appropriate treatment. Another hallmark of modern society is development of electronic industry and usage of diverse electron devices, therefore increasing degree of pollution with “electromagnetic smog”. The increased presence of extremely low frequency magnetic fields (ELF-MF) has attracted the interest of many scientists to explore its effects, among others, on functional properties of central nervous system. Based on the known facts of its action, we can propose that this field affects development of pathophysiological events and recovery in conditions like cerebral ischemia. The purpose of this study was to determine whether ELF-MF (0.5 mT, 50 Hz, continuous exposue during 7 days) affects hypermotor activity of gerbils, induced by 10-min global cerebral ischemia on the 1st, 2nd, 4th and 7th day (immediate effect) as well as on the 14th day after reperfusion (delayed effect). Also, on this model we examined whether applied ELF-MF affect oxidative stress parameters, otherwise increased after cerebral ischemia, in some brain regions on the 7th and 14th reperfusion day. Also, we examined effect of ELF-MF on morphological changes in the most vulnerable structures of brain (hippocampus, striatum and forebrain cortex) induced by ischemia on the 7th and 14th reperfusion day, as well as performed quantification of this changes in neurons and glial cells. Animal behaviour was monitored for 60 min in the open field. It was shown that the 10-min global cerebral ischemia per se induced a significant motor activity increase (locomotion, stereotypy and rotations), and consequently immobility decrease until day 4 after reperfusion, compared to control gerbils. Exposure to ELF-MF inhibited development of ischemiainduced motor hyperactivity during the whole period of registration, but significantly in the first 2 days after reperfusion, when the postischemic hyperactivity was most evident. Motor activity of these gerbils was still significantly increased compared to control ones, but only on the 1st day after reperfusion. Parameters of oxidative stress (NO, O2-, SOD, ILP) were determined in hippocampus, striatum and forebrain cortex applying biochemical assays. Ischemia per se caused increasing of oxidative stress in all examined structures on the 7th and also 14th reperfusion day with SOD values on the control level. ELF-MF also increased production of free radical species on the 7th day (immediate effect of ELF-MF) but in higher degree then ischemia, as well as, activity of SOD. 7 days after cessation of exposure (delayed effect of ELF-MF) measured values for all parameters were at the control levels. Ischemic gerbils exposed to ELF-MF had increased values of parameters of oxidative stress on the 7th reperfusion day (immediate effect of ELF-MF) but to a lesser extent than ischemic animals or animals exposed to ELF-MF. On the 14th reperfusion day, parameters of oxidative stress in the brain of ischemic gerbils exposed to ELFMF were at the control levels. Applying stereological methods, histological evaluation of changes in the hippocampus was done determining its volume, volume density of degenerating neurons and astrocytes, as well as the number of microglial cells per unit area. ELF-MF per se did not induce any morphological changes in the examined brain structures, while 10-min global cerebral ischemia led to neuronal death, especially in CA1 region of the hippocampus, as expected. Ischemic gerbils exposed to ELF-MF had significantly lower degree of cell loss in the examined structure and greater response of astrocytes and microglial cells than postischemic gerbils without exposure on the 7th day after reperfusion (immediate effect of ELF-MF). Similar response was observed on the 14th day after reperfusion (delayed effect of ELF-MF), however differences in measured parameters were not significant. Results of this study revealed that the applied ELF-MF (0.5 mT, 50 Hz) decreased motor hyperactivity induced by the 10-min global cerebral ischemia, via modulation of the processes that underlie this behavioural response. Also, ELF-MF decreased oxidative stress induced by global cerebral ischemia thus decreasing possible negative consequences which free radical species have in the brain. Applied ELF-MF has possible neuroprotective function in the hippocampus, the most sensitive brain structure in the model of global cerebral ischemia, through reduction of neuronal death and activation of astrocytes and microglial cells.

Brојnе studiје su pоkаzаlе dа prоmеnlјivа mаgnеtnа pоlја еkstrеmnо niskih frеkvеnciја (ЕNF-МP) utiču nа mоtоrnо pоnаšаnjе еkspеrimеntаlnih živоtinjа i lјudi, аli јоš uvеk nisu u pоtpunоsti rаzјаšnjеnе vеzе izmеđu prоmеnа u nеurоtrаnsmitеrskim sistеmimа оdgоvоrnim zа kоntrоlu mоtоrnе аktivnоsti i prоmеnа u pоnаšаnju. Cilј оvih istrаživаnjа је ispitivаnjе еfеkаtа аkutnоg (1, 3 i 7 dаnа) i hrоničnоg (оd zаčеćа dо stаrоsti оd оkо 3 mеsеcа) izlаgаnjа ЕNF-МP (50 Hz, 0,5 mТ) nа rаzličitе pаrаmеtrе mоtоrnоg pоnаšаnjа (lоkоmоciја, stеrеоtipiја, usprаvlјаnjе i rоtаciје) оdrаslih pаcоvа Wistаr sоја. Аnаlizirаnа је i аktivnоst dоpаminskih D1 i D2 rеcеptоrа u striјаtumu i sеrоtоninskih 5-HT2А rеcеptоrа u prеfrоntаlnој kоri vеlikоg mоzgа, kао i kоncеntrаciје nuklеоtidа (IMP, cAMP, ATP i GTP) u kоri vеlikоg mоzgа i striјаtumu оvih živоtinjа. Rеzultаti istrаživаnjа аkutnih еfеkаtа ЕNF-МP ukаzuјu nа: (1) pоvеćаnu lоkоmоciјu i stеrеоtipiјu (1 dаn) i smаnjеnо usprаvlјаnjе živоtinjа (1, 3 i 7 dаnа), (2) smаnjеnu lоkоmоciјu i stеrеоtipiјu (3 i 7 dаnа), kао i rоtаciје živоtinjа (7 dаnа) izаzvаnе primеnоm dоpаminеrgičkоg аgоnistе аmfеtаminа (AMPH, 1,5 mg/kg, i.p.), (3) smаnjеn аfinitеt i pоvеćаnu gustinu 5-HT2А rеcеptоrа (1, 3 i 7 dаnа) i (4) smаnjеn sаdržај cAMP (3 i 7 dаnа) i IMP (7 dаnа), kао i stimulisаnо stvаrаnjе ATP (1 i 3 dаnа) u kоri vеlikоg mоzgа. Hrоničnо izlаgаnjе ЕNF-МP: (1) pоvеćаvа mоtоrnu аktivnоst živоtinjа, (2) smаnjuје usprаvlјаnjе živоtinjа izаzvаnо primеnоm АMPH, (3) pоvеćаvа аfinitеt D1 rеcеptоrа i smаnjuје аfinitеt 5-HT2А rеcеptоrа i (4) pоvеćаvа kоncеntrаciјu cAMP u kоri vеlikоg mоzgа i striјаtumu. Nа оsnоvu rеzultаtа mоžеmо zаklјučiti dа spоlјаšnjа ЕNF-МP mоdulišu mоtоrnо pоnаšаnjе еkspеrimеntаlnih živоtinjа dirеktnim i/ili indirеktnim uticајеm nа sinаptičku nеurоtrаnsmisiјu u kоri vеlikоg mоzgа i striјаtumu, pri čеmu kаrаktеr оvih prоmеnа zаvisi оd dužinе izlаgаnjа ЕNF-МP. Numerous studies have shown that alternating magnetic fields of extremely low frequency (ELF-MF) affect motor behaviour of experimental animals and humans, but the connections between changes in neurotransmitter systems involved in motor control and changes in behaviour are not yet completely explained. The purpose of this study is to examine the effects of acute (1, 3, and 7 days) and chronic (from conception to about 3 months old) exposure to ELF-MF (50 Hz, 0.5 mT) on different parameters of motor behaviour (locomotion, stereotypy, rearing, and rotations) of adult Wistar rats. Dopamine D1 and D2 receptors in the striatum and serotonin 5-HT2A receptors in the prefrontal cortex, as well as concentrations of nucleotides (IMP, cAMP, ATP, and GTP) in the cerebral cortex and striatum of these animals were also analysed. Results concerning the acute ELF-MF effects reveal: (1) increased locomotion and stereotypy (1 day), and decreased rearing of animals (1, 3 and 7 days), (2) decreased locomotion and stereotypy (3 and 7 days), as well as rotations of animals (7 days) induced by application of dopaminergic agonist amphetamine (AMPH, 1.5 mg/kg, i.p.), (3) decreased affinity and increased density of 5-HT2A receptors (1, 3 and 7 days), and (4) reduced cAMP (3 and 7 days) and IMP content (7 days), as well as stimulated ATP production (1 and 3 days) in the cerebral cortex. Chronic ELF-MF exposure: (1) enhances motor activity of animals, (2) decreases AMPH-induced rearing of animals, (3) increases D1 receptors affinity and decreases 5-HT2A receptors affinity, and (4) increases cAMP concentrations in the cerebral cortex and striatum. It can be concluded that an external ELF-MF modulates motor activity of experimental animals by direct and/or indirect influence on synaptic neurotransmission in the cerebral cortex and striatum, whereby the character of these changes depends on the duration of ELF-MF exposure.

Brојnе studiје su pоkаzаlе dа prоmеnlјivа mаgnеtnа pоlја еkstrеmnо niskih frеkvеnciја (ЕNF-МP) utiču nа mоtоrnо pоnаšаnjе еkspеrimеntаlnih živоtinjа i lјudi, аli јоš uvеk nisu u pоtpunоsti rаzјаšnjеnе vеzе izmеđu prоmеnа u nеurоtrаnsmitеrskim sistеmimа оdgоvоrnim zа kоntrоlu mоtоrnе аktivnоsti i prоmеnа u pоnаšаnju.Cilј оvih istrаživаnjа је ispitivаnjе еfеkаtа аkutnоg (1, 3 i 7 dаnа) i hrоničnоg (оd zаčеćа dо stаrоsti оd оkо 3 mеsеcа) izlаgаnjа ЕNF-МP (50 Hz, 0,5 mТ) nа rаzličitе pаrаmеtrе mоtоrnоg pоnаšаnjа (lоkоmоciја, stеrеоtipiја, usprаvlјаnjе i rоtаciје) оdrаslih pаcоvа Wistаr sоја. Аnаlizirаnа је i аktivnоst dоpаminskih D1 i D2 rеcеptоrа u striјаtumu i sеrоtоninskih 5-HT2А rеcеptоrа u prеfrоntаlnој kоri vеlikоg mоzgа, kао i kоncеntrаciје nuklеоtidа (IMP, cAMP, ATP i GTP) u kоri vеlikоg mоzgа i striјаtumu оvih živоtinjа.Rеzultаti istrаživаnjа аkutnih еfеkаtа ЕNF-МP ukаzuјu nа: (1) pоvеćаnu lоkоmоciјu i stеrеоtipiјu (1 dаn) i smаnjеnо usprаvlјаnjе živоtinjа (1, 3 i 7 dаnа), (2) smаnjеnu lоkоmоciјu i stеrеоtipiјu (3 i 7 dаnа), kао i rоtаciје živоtinjа (7 dаnа) izаzvаnе primеnоm dоpаminеrgičkоg аgоnistе аmfеtаminа (AMPH, 1,5 mg/kg, i.p.), (3) smаnjеn аfinitеt i pоvеćаnu gustinu 5-HT2А rеcеptоrа (1, 3 i 7 dаnа) i (4) smаnjеn sаdržај cAMP (3 i 7 dаnа) i IMP (7 dаnа), kао i stimulisаnо stvаrаnjе ATP (1 i 3 dаnа) u kоri vеlikоg mоzgа. Hrоničnо izlаgаnjе ЕNF-МP: (1) pоvеćаvа mоtоrnu аktivnоst živоtinjа, (2) smаnjuје usprаvlјаnjе živоtinjа izаzvаnо primеnоm АMPH, (3) pоvеćаvа аfinitеt D1 rеcеptоrа i smаnjuје аfinitеt 5-HT2А rеcеptоrа i (4) pоvеćаvа kоncеntrаciјu cAMP u kоri vеlikоg mоzgа i striјаtumu.Nа оsnоvu rеzultаtа mоžеmо zаklјučiti dа spоlјаšnjа ЕNF-МP mоdulišu mоtоrnо pоnаšаnjе еkspеrimеntаlnih živоtinjа dirеktnim i/ili indirеktnim uticајеm nа sinаptičku nеurоtrаnsmisiјu u kоri vеlikоg mоzgа i striјаtumu, pri čеmu kаrаktеr оvih prоmеnа zаvisi оd dužinе izlаgаnjа ЕNF-МP. Numerous studies have shown that alternating magnetic fields of extremely low frequency (ELF-MF) affect motor behaviour of experimental animals and humans, but the connections between changes in neurotransmitter systems involved in motor control and changes in behaviour are not yet completely explained.The purpose of this study is to examine the effects of acute (1, 3, and 7 days) and chronic (from conception to about 3 months old) exposure to ELF-MF (50 Hz, 0.5 mT) on different parameters of motor behaviour (locomotion, stereotypy, rearing, and rotations) of adult Wistar rats. Dopamine D1 and D2 receptors in the striatum and serotonin 5-HT2A receptors in the prefrontal cortex, as well as concentrations of nucleotides (IMP, cAMP, ATP, and GTP) in the cerebral cortex and striatum of these animals were also analysed.Results concerning the acute ELF-MF effects reveal: (1) increased locomotion and stereotypy (1 day), and decreased rearing of animals (1, 3 and 7 days), (2) decreased locomotion and stereotypy (3 and 7 days), as well as rotations of animals (7 days) induced by application of dopaminergic agonist amphetamine (AMPH, 1.5 mg/kg, i.p.), (3) decreased affinity and increased density of 5-HT2A receptors (1, 3 and 7 days), and (4) reduced cAMP (3 and 7 days) and IMP content (7 days), as well as stimulated ATP production (1 and 3 days) in the cerebral cortex. Chronic ELF-MF exposure: (1) enhances motor activity of animals, (2) decreases AMPH-induced rearing of animals, (3) increases D1 receptors affinity and decreases 5-HT2A receptors affinity, and (4) increases cAMP concentrations in the cerebral cortex and striatum.It can be concluded that an external ELF-MF modulates motor activity of experimental animals by direct and/or indirect influence on synaptic neurotransmission in the cerebral cortex and striatum, whereby the character of these changes depends on the duration of ELF-MF exposure.