|
|
Study of selected mushroom toxins of Amanita muscaria.
Adámek, Michal ; Bosáková, Zuzana (advisor) ; Hložek, Tomáš (referee)
The presented bachelor's thesis was focused on the development of an HPLC-MS/MS method for the separation and eventual quantification of the main toxins of Amanita muscaria (fly agaric). After optimization of tandem mass detection conditions, MRM transitions were found for muscarine (174 → 57), ibotenic acid (159 → 113), muscimol (115 → 98) and cycloserine (103 → 75), which was used as an internal standard. Measurements were performed on Luna Omega 1.6 µm polar C18 column in RP-HPLC mode with an optimized mobile phase composition of 2:98 (v/v) acetonitrile/deionized water with the addition of 0.1% formic acid in both components and Ascentis Express RP- Amide in HILIC mode with an optimized mobile phase composed of 70:30 (v/v) methanol/deionized water with the addition of 0.5% formic acid in both components. Calibration curves with a range of 0.01 to 10 µg/ml for RP-HPLC and 0.01 to 25 µg/ml for HILIC were measured under optimized conditions. Urine and blood serum solutions of a patient with Amanita muscaria poisoning, including diluted versions of these solutions, were measured. Ibotenic acid and muscimol were found in the patient's urine, muscarine, ibotenic acid and muscimol in the blood serum. The RP-HPLC method gave narrower peaks with lower retentions and lower noise levels. The studied toxins...
|
|
|
Role of ventral hippocampus and medial prefrontal cortex in behavioral flexibility in rodents
Černotová, Daniela ; Svoboda, Jan (advisor) ; Telenský, Petr (referee)
Behavioral adaptation to a continuously changing environment is critical for the survival of the animals, but also day-to-day interactions in the human world. The main components maintaining flexibility in cognition and behavior are well-established and depend mostly on proper intercommunication within the prefrontal cortex (PFC) and striatum. Some parts of the PFC are densely innervated by the ventral hippocampus (vHPC), which has a great impact on its functioning. Also, hippocampal-prefrontal circuit dysfunction has been shown to disrupt the integrity of flexible cognition in some neuropsychiatric diseases. Therefore, the exact functional role of this pathway is an indispensable part of the research. The aim of this study was to test the role of the vHPC and the medial PFC (mPFC) in an active place avoidance task on a rotating arena in 1) two flexibility task variants - reversal learning and set- shifting - and 2) the spatial memory retrieval. We inactivated these structures by muscimol (GABAA receptor agonist) in a variety of unilateral, bilateral, and combined local injections. Disrupted performance was apparent in reversal learning in vHPC-inactivated rats. No effect was seen in mPFC-inactivated rats. Impairments after the task acquisition were observed in bilateral vHPC and mPFC inactivations...
|
|
|
Role of ventral hippocampus and medial prefrontal cortex in behavioral flexibility in rodents
Černotová, Daniela ; Svoboda, Jan (advisor) ; Telenský, Petr (referee)
Behavioral adaptation to a continuously changing environment is critical for the survival of the animals, but also day-to-day interactions in the human world. The main components maintaining flexibility in cognition and behavior are well-established and depend mostly on proper intercommunication within the prefrontal cortex (PFC) and striatum. Some parts of the PFC are densely innervated by the ventral hippocampus (vHPC), which has a great impact on its functioning. Also, hippocampal-prefrontal circuit dysfunction has been shown to disrupt the integrity of flexible cognition in some neuropsychiatric diseases. Therefore, the exact functional role of this pathway is an indispensable part of the research. The aim of this study was to test the role of the vHPC and the medial PFC (mPFC) in an active place avoidance task on a rotating arena in 1) two flexibility task variants - reversal learning and set- shifting - and 2) the spatial memory retrieval. We inactivated these structures by muscimol (GABAA receptor agonist) in a variety of unilateral, bilateral, and combined local injections. Disrupted performance was apparent in reversal learning in vHPC-inactivated rats. No effect was seen in mPFC-inactivated rats. Impairments after the task acquisition were observed in bilateral vHPC and mPFC inactivations...
|
|
| |
guest ::
