The perinatal period of life is a critical moment for a proper development of CNS, however it is a risky period, which is associated with many pathologies. Hence, it is important to acquire knowledge and combine new methodologies for understanding the developmental aspects of physiology/pathophysiology of the brain. We have successfully developed and applied the method of monitoring a tissue metabolism in the immature brain. Using a combination of microdialysis technique and HPLC-MS basal levels of amino acids and other low molecular weight molecules in the hippocampus of immature rats (12-days-old) were mapped. Our results demonstrate the suitability of chosen parameters of sampling and analysis for the monitoring of tissue biochemistry and metabolomic mapping in immature brain. Moreover, a potential of the proposed method can found a place in clinical practice and for biomarkers monitoring of various CNS diseases.
- MeSH
- aminokyseliny MeSH
- mikrodialýza * využití MeSH
- mozek * metabolismus MeSH
- potkani Wistar MeSH
- vysokoúčinná kapalinová chromatografie využití MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
Mikrodialýza (MD) v kombinaci s vysokoúčinnou kapalinovou chromatografií a hmotnostní spektrometrií (HPLC-MS) je úspěšně využí- vána k metabolomickému mapování dynamických změn v mozku. Potřeba využití těchto metod vzrůstá s rozvojem nových syntetických drog (NSD), kdy je nutné na jejich výskyt velmi rychle reagovat a určit jejich případnou nebezpečnost a jejich adiktivní potenciál. Z uvedeného důvodu by tato metodika mohla v budoucnu sloužit jako prediktivní nástroj pro určení nebezpečnosti NSD na základě metabolických změn v průběhu intoxikace. Dovolujeme si odhadnout, že tato metoda má vysoký potenciál pro rozšíření znalostí nejen o účinku nových syntetických drog (NSD) a molekulární podstatě rozvoje závislosti, ale může také posloužit k vývoji nových léčebných postupů.
In the past decades, the requirement for in vivo detection of diverse chemical substances has increased due to development of new synthetic drugs with an unknown impact on brain metabolism. Microdialysis in combination with high -performance liquid chromatography and mass spectrometry (HPLC-MS) is an efficient tool for monitoring dynamic biochemical changes in the brain. Hence, it could be used for dissecting the mechanism of action of newly appearing synthetic abusive drugs and processes involved in the development of drug addiction. Moreover, it can be optimized for diverse compounds and biological tissues and utilized, for example, for testing of novel therapeutical approaches.
- MeSH
- dopamin sekrece MeSH
- hmotnostní spektrometrie MeSH
- metabolomika MeSH
- methamfetamin farmakologie MeSH
- mikrodialýza * MeSH
- mozek metabolismus MeSH
- poruchy spojené s užíváním psychoaktivních látek * metabolismus MeSH
- potkani Wistar MeSH
- vysokoúčinná kapalinová chromatografie * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
The present study has examined the anticonvulsant and neuroprotective effect of 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC), a selective agonist for group II metabotropic glutamate receptors (mGluRs) when given 10-15 min after the onset of seizures induced in 12-day-old rats by bilateral icv infusion of DL-homocysteic acid (DL-HCA, 600 nmol/side). For biochemical analyses, rat pups were sacrificed during generalized clonic-tonic seizures, approximately 45-50 min after infusion of DL-HCA. Comparable time intervals were used for sacrificing the animals which received 2R,4R-APDC (0.05 nmol/side) or saline. The severity of seizures was influenced only slightly when the agonist was given after the onset of seizures, as evaluated both from the behavioral symptoms and from EEG recordings. A tendency to lower number and a shorter duration of seizures was outlined in animals posttreated with 2R,4R-APDC, but the differences did not reach the level of statistical significance. Cortical energy metabolite changes which normally accompany seizures in immature rats (large decrease of glucose and glycogen and a marked rise of lactate) were ameliorated only partially. The neuroprotective effect of 2R,4R-APDC was evaluated after 24 h and 6 days of survival following DL-HCA-induced seizures. Massive neuronal degeneration in many brain regions, mainly in the hippocampus and thalamus, following infusion of DL-HCA alone was only partially attenuated after 2R,4R-APDC posttreatment. The present findings clearly indicate that both anticonvulsant and neuroprotective effect of 2R,4R-APDC against DL-HCA-induced seizures is substantially diminished when the agonist is given after the onset of seizures as compared with its efficacy after the pretreatment (Exp. Neurol.192, 420-436, 2005).
- MeSH
- agonisté excitačních aminokyselin terapeutické užití MeSH
- cytoprotekce fyziologie účinky léků MeSH
- degenerace nervu chemicky indukované patofyziologie prevence a kontrola MeSH
- epilepsie farmakoterapie metabolismus patofyziologie MeSH
- hipokampus metabolismus růst a vývoj účinky léků MeSH
- homocystein analogy a deriváty farmakologie MeSH
- konvulzíva farmakologie MeSH
- krysa rodu rattus MeSH
- lékové interakce fyziologie MeSH
- mozek metabolismus růst a vývoj účinky léků MeSH
- neuroprotektivní látky terapeutické užití MeSH
- potkani Wistar MeSH
- prolin analogy a deriváty terapeutické užití MeSH
- receptory metabotropního glutamátu agonisté metabolismus MeSH
- rozvrh dávkování léků MeSH
- stárnutí metabolismus MeSH
- thalamus metabolismus růst a vývoj účinky léků MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
Lithium-pilocarpine status epilepticus (SE) resulted in delayed changes of single cortical interhemisperic (transcallosal) responses in immature rats. Low-frequency stimulation inducing depression and/or potentiation was studied to analyze possible dynamic changes in cortical responses. Status was elicited in 12-day-old (SE12) or 25-day-old (SE25) rats. Control siblings received saline instead of pilocarpine. Interhemispheric responses were elicited by stimulation of the sensorimotor region of the cerebral cortex 3, 6, 9, 13, or 26 days after status. A series of 5 biphasic pulses with intensity equal to twofold threshold were used for stimulation. The interval between pulses was 100, 125, 160, 200 or 300 ms, eight responses were always averaged. Peak amplitude of the first positive, first negative and second positive waves was measured and responses to the second, third, fourth and fifth pulse were compared with the first one. Animals after status epilepticus as well as lithium-paraldehyde controls exhibit a frequency depression at nearly all the intervals studied. An outlined increase of responses in SE rats in comparison with the controls three days after SE stayed just below the level of statistical significance. In addition, animals in the SE12 group exhibited potentiation of responses at this interval after SE. With longer intervals after SE, the relation between SE and control animals changed twice resulting in a tendency to lower amplitude of responses in SE than in control rats 26 days after SE. Rats in the SE25 group exhibited higher responses than controls 13 days after status, but this difference was not present at the longest interval after SE. Low-frequency stimulation did not reveal increased cortical excitability as a long-lasting consequence of status epilepticus induced in immature rats. In addition, the outlined differences between SE and control rats changed with the time after SE.
- MeSH
- deprese etiologie patofyziologie MeSH
- epilepsie enzymologie etiologie patofyziologie MeSH
- evokované potenciály účinky léků MeSH
- financování organizované MeSH
- implantované elektrody virologie MeSH
- interpretace statistických dat MeSH
- pilokarpin škodlivé účinky MeSH
- potkani Wistar MeSH
- vývojová biologie metody MeSH
The goal of this study was to develop a new model of ischemia-induced seizures in immature rats using injection of vasoconstrictor Endothelin-1 (ET-1) into the brain. ET-1 (10, 20, or 40 pmol) was infused into the left dorsal hippocampus of freely moving Wistar rats 12 (P12) and 25 (P25) days old. Animals were then video/EEG-monitored for 100 min and monitoring was repeated 22 h later. Parameters of electrographic seizures (frequency and mean duration) as well as pattern of their behavioral correlates were evaluated. The pattern of behavioral seizures was used to develop model-specific scoring system. Cresyl violet and Fluoro Jade-B-staining were used to evaluate brain damage. Extension of the lesion was correlated with seizure severity. After ET-1-injection, seizures occurred in 83-100% animals of all age-and-dose groups and persisted for 24 h except P12 rats with 10 pmol. There were no differences in average seizure duration (18-40 s) or seizure frequency (3-7 seizures/100 min) among individual dose-groups. Between the 1st and 2nd observation period, total seizure duration decreased in 71% of P12 and 47% of P25 rats. Electrographic seizure activity was most frequently accompanied by clonus, incidence of more severe convulsions (barrel rolling or generalized clonic seizures) increased with dose of ET-1. Morphologic examination did not reveal any dose-related difference in damage severity, hippocampal damage was however more extensive in P12 compared to P25 animals. Seizure severity correlated positively with severity of the damage in both age groups. Our study presents focal injection of ET-1 into the brain as a new and practical model of ischemia-induced seizures in immature rats.
- MeSH
- elektroencefalografie statistika a číselné údaje MeSH
- endotelin-1 aplikace a dávkování farmakologie MeSH
- epilepsie chemicky indukované patofyziologie patologie MeSH
- financování organizované MeSH
- hipokampus patofyziologie patologie účinky léků MeSH
- injekce MeSH
- ischemie mozku chemicky indukované patofyziologie patologie MeSH
- krysa rodu rattus MeSH
- novorozená zvířata MeSH
- potkani Wistar MeSH
- videozáznam MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
The direct injection of endothelin-1 (ET-1) into brain parenchyma was recently suggested as a suitable model of stroke. The present study was designed to assess whether intrahippocampal injection of ET-1 in immature rats causes neurodegeneration and immediate seizures, and results in impairment of motor development, cognitive decline, epilepsy and chronic hippocampal lesion. ET-1 was injected unilaterally into the dorsal hippocampus in doses of 20 or 40 pmol at the age of 12 (P12) or 25 (P25) days. Video-electroencephalographic monitoring performed during 100 min after the injection of ET-1 demonstrated the development of convulsive epileptic seizures in 75-100% of animals of individual age-and-dose groups. Long-term behavioral follow-up did not reveal impairment of motor development in any dose-and-age group. At 2 months after ET-1 injection, impairment of spatial memory occurred only in rats with 40 pmol of ET-1 at P12. At 3 months after ET-1 injection spontaneous electrographic seizures occurred in 62.5-100% animals of both ages with no relation to the dose used. Seizures were always non-convulsive. The total seizure duration per 24 h was higher in the P12 than the P25 group, suggesting more severe epilepsy. The extent of the hippocampal lesion increased with the dose of ET-1 and was significantly higher in the P12 than the P25 group. The severity of the ET-1-induced lesion correlated positively with total seizure duration per 24 h at both ages. Our results document that early intrahippocampal injection of ET-1 results in lesion development and both immediate seizures and chronic epilepsy in either age group. Cognitive impairment occurred only in rats with ET-1 injection at P12.
- MeSH
- arteriae cerebrales patofyziologie účinky léků MeSH
- cévní mozková příhoda chemicky indukované komplikace patofyziologie MeSH
- degenerace nervu chemicky indukované patofyziologie patologie MeSH
- elektroencefalografie účinky léků MeSH
- endotelin-1 škodlivé účinky MeSH
- epilepsie chemicky indukované patofyziologie MeSH
- financování organizované MeSH
- hipokampus patofyziologie patologie účinky léků MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- mozková hypoxie a ischemie chemicky indukované komplikace patofyziologie MeSH
- mozkový krevní oběh účinky léků MeSH
- novorozená zvířata MeSH
- novorozenec MeSH
- poruchy paměti chemicky indukované patofyziologie MeSH
- potkani Wistar MeSH
- rozvrh dávkování léků MeSH
- vazokonstriktory škodlivé účinky MeSH
- věkové faktory MeSH
- vývojové poruchy u dětí chemicky indukované patofyziologie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- zvířata MeSH
