EFFECT OF PERINATAL CHANGES IN SEROTONIN METABOLISM ON THE DEVELOPMENT AND BEHAVIOUR OF RAT PUPS

Serotonin (5HT) je biogeni amin prisutan u mozgu (središnji odjeljak) i tjelesnim tkivima (periferni odjeljak) gdje ima različite fiziološke uloge. U ovom radu ispitali smo utjecaj perinatalnog povećanja koncentracije serotonina na stopu preživljenja, prirast tjelesne mase i anksiozno ponašanje mladunaca štakora. Životinje smo tretirali od 13.gestacijskog do 21. postnatalnog dana prekursorom serotonina, 5-hidroksitriptofanom (5-HTP) ili inhibitorom razgradnje serotonina, tranilciprominom (TCP). Kontrolnu skupinu tretirali smo fiziološkom otopinom. Obje eksperimentalne skupine su imale znatno smanjenu stopu preživljenja, dok su preživjeli mladunci imali značajno manju masu, kao i njezin prirast, u odnosu na kontrolnu skupinu. Anksiozno ponašanje pratili smo testom ultrazvučnog dozivanja nakon izdvajanja iz legla 13., 16. i 18. postnatalnog dana. Životinje tretirane TCP-om imale su značajno kraće vrijeme latencije do prvog doziva, te znatno veći ukupni broj doziva, broj sljedova doziva i trajanje doziva. U životinja tretiranih 5HTP-om ove su vrijednosti bile slične kontrolnima. U obje eksperimentalne skupine došlo je do kasnijeg prebacivanja frekvencije ultrazvučnog dozivanja s infantilne (40 kHz) na juvenilnu (50 kHz). Rezultati upućuju na to da povišena koncentracija serotonina u doba perinatalnog razvoja negativno djeluje na razvoj mladunaca, povećava razinu anksioznosti i odgađa sazrijevanje mladunaca. Pri tome je učinak TCP-a, koji povisuje koncentraciju 5HT u oba odjeljka, drastičniji od učinka 5-HTP-a koji povisuje koncentraciju 5HT samo u perifernom odjeljku.Serotonin (5HT) is a biogenic amine present both in the brain (central compartment) and in peripheral tissues (peripheral compartment) where it has different physiological functions. In this thesis we have studied the influence of perinatal increase in serotonin concentrations on survival rate, weight gain and anxiety-like behavior in rat pups. The animals were treated with serotonin precursor 5-hydroxytryptophan (5-HTP) or with serotonin catabolism inhibitor tranylcypromine (TCP) from gestational day 13 to post-natal day 21. Control group was treated with saline. Both experimental groups had significantly lower survival rates, while the survived pups had significantly lower body mass and weight gain compared to the control group. Anxiety-like behavior was determined by analyzing ultrasonic vocalization after separation from litter on post-natal days 13, 16 and 18. TCP-treated animals had significantly reduced latency to the first call and significantly higher number of calls, number of call sequences and duration of calls. In animals treated with 5HTP, these values were similar to those of the control group. A delay in frequency transition from infantile (40 kHz) to juvenile (50 kHz) was observed in both experimental groups. The results suggest that exposure to increased serotonin concentrations during perinatal period negatively affects rat development, increases the level of anxiety and delays maturation. The effect of TCP, which raises serotonin level in both 5HT compartments, is more drastic than the effect of 5HTP, which raises serotonin concentration only in the peripheral compartment

Population of wild boars (Sus scrofa Linnaeus, 1758) in Croatia

Divlje svinja (Sus scrofa L.) je vrsta iz reda papkara, koja živi nomadskim životom. Ženke ove vrste žive u čoporu skupa sa mladima, na čelu kojeg se uvijek nalazi najstarija ženka, dok odrasli mužjaci žive usamljeničkim načinom života. Najsnažniji mužjak dolazi do krda isključivo u vrijeme parenja, a nakon kojeg ponovno odlazi živjeti samostalno. U jednom leglu se javlja najviše pet mladih. Ova vrsta je svežder, hrani se hranom biljnog i životinjskog porijekla, pa čak i strvinom. Divlja svinja je u Hrvatskoj autohtona vrsta, čija brojnost populacije varira tijekom godina. Na brojnost ove vrste utječe nekoliko čimbenika, ali najvažniji je čovjek. Ljudi love divlje svinje zbog mesa, trofeja, ali i zbog štete koju ova vrsta uzrokuje na poljoprivrednim površinama. Tijekom suše divlje svinje dolaze do održavanih površina u potrazi za hranom, te na taj način uzrokuju novčane gubitke poljoprivrednicima. U zadnjih dvadesetak godina u Hrvatskoj su se pojavili hibridi nastali križanjem divljih i domaćih svinja. Ovi hibridi su fenotipom sličniji divljim svinjama, ali imaju više mladih, daju potomstvo tokom cijele godine i slabije su otporni na virusne i parazitske bolesti.Wild boar (Sus scrofa L.) is a species from the order of ungulates, which lives a nomadic life. Females of this species live in the pack along with the youth, led by the eldest female, while adult males live solitary way of life. The strongest male comes in a pack only during mating season, after whitch he goes back tu live independently. There is a maximum of five youth in one litter. This species is omnivorous, feeding on food of plant and animal origin, and even carrion. Wild boar is a native species in Croatia, whose population number variates over the years. There are several factors that influence on the abundance of this species, but the most important one is the man. People hunt wild boars fot meat and trophies, but also because of the damage caused by this species in agricultural areas. During the drought wild boars arrive in cultivable areas in search for food, thus causing financial losses to farmers. In the last twenty years hybrids created by pairing wild boars and domestic pigs appeared in Croatia. These hybrids have similar phenotype to wild boars, but they have more youth, give progeny throughout the year, and are less resistant to viral and parasitic diseases

Determining the impact of neocortex size changes on information processing : implications for neurodevelopmental disorders

Development of the cerebral cortex is highly regulated by genetically programmed sequential events. Alterations in this process by genetic or non-genetic factors can lead to over- or underproduction of cortical neurons and abnormal connectivity, resulting in neurodevelopmental disorders, such as autism spectrum disorder (ASD). Although ASD patients often exhibit atypical sensory processing, the relationship between abnormal cortical size and sensory processing is still unclear. Here we hypothesise that abnormal cortical expansion during development leads to atypical sensory processing. To test this hypothesis, we utilized a recently established mouse model, in which the number of superficial cortical excitatory neurons is increased pharmacologically during embryonic development. This mouse model is also known to exhibit macrocephaly and autism-like phenotypes. In this project, we assessed their auditory perception behaviourally and evaluated neuronal population activity in the auditory cortex and medial geniculate nucleus through high-density in vivo electrophysiological recording. Our results indicate that the overproduction of superficial cortical excitatory neurons negatively affects auditory processing. Treated mice exhibited hyposensitivity to near-threshold auditory stimuli during behavioural auditory detection assessment. Further, their cortical neurons showed lower spontaneous and auditory evoked activity as well as delayed peak response latency. We also observed atypical cortical functional connectivity. Overall, our study suggests that abnormal cortical expansion during development results in atypical auditory processing, and provides further insights into the neural basis of perceptual deficits in neurodevelopmental disorders such as ASD.Development of the cerebral cortex is highly regulated by genetically programmed sequential events. Alterations in this process by genetic or non-genetic factors can lead to over- or underproduction of cortical neurons and abnormal connectivity, resulting in neurodevelopmental disorders, such as autism spectrum disorder (ASD). Although ASD patients often exhibit atypical sensory processing, the relationship between abnormal cortical size and sensory processing is still unclear. Here we hypothesise that abnormal cortical expansion during development leads to atypical sensory processing. To test this hypothesis, we utilized a recently established mouse model, in which the number of superficial cortical excitatory neurons is increased pharmacologically during embryonic development. This mouse model is also known to exhibit macrocephaly and autism-like phenotypes. In this project, we assessed their auditory perception behaviourally and evaluated neuronal population activity in the auditory cortex and medial geniculate nucleus through high-density in vivo electrophysiological recording. Our results indicate that the overproduction of superficial cortical excitatory neurons negatively affects auditory processing. Treated mice exhibited hyposensitivity to near-threshold auditory stimuli during behavioural auditory detection assessment. Further, their cortical neurons showed lower spontaneous and auditory evoked activity as well as delayed peak response latency. We also observed atypical cortical functional connectivity. Overall, our study suggests that abnormal cortical expansion during development results in atypical auditory processing, and provides further insights into the neural basis of perceptual deficits in neurodevelopmental disorders such as ASD

Population of wild boars (Sus scrofa Linnaeus, 1758) in Croatia

Divlje svinja (Sus scrofa L.) je vrsta iz reda papkara, koja živi nomadskim životom. Ženke ove vrste žive u čoporu skupa sa mladima, na čelu kojeg se uvijek nalazi najstarija ženka, dok odrasli mužjaci žive usamljeničkim načinom života. Najsnažniji mužjak dolazi do krda isključivo u vrijeme parenja, a nakon kojeg ponovno odlazi živjeti samostalno. U jednom leglu se javlja najviše pet mladih. Ova vrsta je svežder, hrani se hranom biljnog i životinjskog porijekla, pa čak i strvinom. Divlja svinja je u Hrvatskoj autohtona vrsta, čija brojnost populacije varira tijekom godina. Na brojnost ove vrste utječe nekoliko čimbenika, ali najvažniji je čovjek. Ljudi love divlje svinje zbog mesa, trofeja, ali i zbog štete koju ova vrsta uzrokuje na poljoprivrednim površinama. Tijekom suše divlje svinje dolaze do održavanih površina u potrazi za hranom, te na taj način uzrokuju novčane gubitke poljoprivrednicima. U zadnjih dvadesetak godina u Hrvatskoj su se pojavili hibridi nastali križanjem divljih i domaćih svinja. Ovi hibridi su fenotipom sličniji divljim svinjama, ali imaju više mladih, daju potomstvo tokom cijele godine i slabije su otporni na virusne i parazitske bolesti.Wild boar (Sus scrofa L.) is a species from the order of ungulates, which lives a nomadic life. Females of this species live in the pack along with the youth, led by the eldest female, while adult males live solitary way of life. The strongest male comes in a pack only during mating season, after whitch he goes back tu live independently. There is a maximum of five youth in one litter. This species is omnivorous, feeding on food of plant and animal origin, and even carrion. Wild boar is a native species in Croatia, whose population number variates over the years. There are several factors that influence on the abundance of this species, but the most important one is the man. People hunt wild boars fot meat and trophies, but also because of the damage caused by this species in agricultural areas. During the drought wild boars arrive in cultivable areas in search for food, thus causing financial losses to farmers. In the last twenty years hybrids created by pairing wild boars and domestic pigs appeared in Croatia. These hybrids have similar phenotype to wild boars, but they have more youth, give progeny throughout the year, and are less resistant to viral and parasitic diseases

Population of wild boars (Sus scrofa Linnaeus, 1758) in Croatia

Divlje svinja (Sus scrofa L.) je vrsta iz reda papkara, koja živi nomadskim životom. Ženke ove vrste žive u čoporu skupa sa mladima, na čelu kojeg se uvijek nalazi najstarija ženka, dok odrasli mužjaci žive usamljeničkim načinom života. Najsnažniji mužjak dolazi do krda isključivo u vrijeme parenja, a nakon kojeg ponovno odlazi živjeti samostalno. U jednom leglu se javlja najviše pet mladih. Ova vrsta je svežder, hrani se hranom biljnog i životinjskog porijekla, pa čak i strvinom. Divlja svinja je u Hrvatskoj autohtona vrsta, čija brojnost populacije varira tijekom godina. Na brojnost ove vrste utječe nekoliko čimbenika, ali najvažniji je čovjek. Ljudi love divlje svinje zbog mesa, trofeja, ali i zbog štete koju ova vrsta uzrokuje na poljoprivrednim površinama. Tijekom suše divlje svinje dolaze do održavanih površina u potrazi za hranom, te na taj način uzrokuju novčane gubitke poljoprivrednicima. U zadnjih dvadesetak godina u Hrvatskoj su se pojavili hibridi nastali križanjem divljih i domaćih svinja. Ovi hibridi su fenotipom sličniji divljim svinjama, ali imaju više mladih, daju potomstvo tokom cijele godine i slabije su otporni na virusne i parazitske bolesti.Wild boar (Sus scrofa L.) is a species from the order of ungulates, which lives a nomadic life. Females of this species live in the pack along with the youth, led by the eldest female, while adult males live solitary way of life. The strongest male comes in a pack only during mating season, after whitch he goes back tu live independently. There is a maximum of five youth in one litter. This species is omnivorous, feeding on food of plant and animal origin, and even carrion. Wild boar is a native species in Croatia, whose population number variates over the years. There are several factors that influence on the abundance of this species, but the most important one is the man. People hunt wild boars fot meat and trophies, but also because of the damage caused by this species in agricultural areas. During the drought wild boars arrive in cultivable areas in search for food, thus causing financial losses to farmers. In the last twenty years hybrids created by pairing wild boars and domestic pigs appeared in Croatia. These hybrids have similar phenotype to wild boars, but they have more youth, give progeny throughout the year, and are less resistant to viral and parasitic diseases

Pontine waves accompanied by short hippocampal sharp wave-ripples during non-rapid eye movement sleep : P-waves during NREM and REM sleep

Ponto-geniculo-occipital (PGO) or pontine (P) waves have long been recognized as an electrophysiological signature of rapid eye movement (REM) sleep. However, P-waves can be observed not just during REM sleep, but also during non-REM (NREM) sleep. Recent studies have uncovered that P-waves are functionally coupled with hippocampal sharp wave-ripples (SWRs) during NREM sleep. However, it remains unclear to what extent P-waves during NREM sleep share their characteristics with P-waves during REM sleep and how the functional coupling to P-waves modulates SWRs. Here, we address these issues by performing multiple types of electrophysiological recordings and fiber photometry in both sexes of mice. P-waves during NREM sleep share their waveform shapes and local neural ensemble dynamics at a short (~100 ms) timescale with their REM sleep counterparts. However, the dynamics of mesopontine cholinergic neurons are distinct at a longer (~10 s) timescale: although P-waves are accompanied by cholinergic transients, the cholinergic tone gradually reduces before P-wave genesis during NREM sleep. While P-waves are coupled to hippocampal theta rhythms during REM sleep, P-waves during NREM sleep are accompanied by a rapid reduction in hippocampal ripple power. SWRs coupled with P-waves are short-lived and hippocampal neural firing is also reduced after P-waves. These results demonstrate that P-waves are part of coordinated sleep-related activity by functionally coupling with hippocampal ensembles in a state-dependent manner