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4532. Changes of calcium binding protein expression in spinothalamic tract neurons after peripheral inflammation
- Creator:
- David Sojka, Gabriela Zacharová, D. Spicarova, and Jiří Paleček
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, artritida, arthritis, calbindin, parvalbumin, calretinin, synaptic plasticity, 14, and 612
- Language:
- English
- Description:
- Specific neuronal populations are known to express calcium binding proteins (CBP) such as calbindin (CB), parvalbumin (PV) and calretinin (CR). These CBP can act as calcium buffers that modify spatiotemporal characteristics of intracellular calcium transients and affect calcium homeostasis in neurons. It was recently shown that changes in neuronal CBP expression can have significant modulatory effect on synaptic transmission. Spinothalamic tract (STT) neurons form a major nociceptive pathway and they become sensitized after peripheral inflammation. In our experiments, expression of CBP in STT neurons was studied in a model of unilateral acute knee joint arthritis in rats. Altogether 377, 374 and 358 STT neurons in the segments L3-4 were evaluated for the presence of CB, PV and CR. On the contralateral (control) side 11 %, 9 % and 47 % of the retrogradely labeled STT ne urons expressed CB, PV and CR, respectively. On the ipsilateral (arthritic) side there was significantly more CB (23 %) and PV (25 %) expressing STT neurons, while the number of CR positive neurons (50 %) did not differ. Our results show increased expression of fast (CB) and slow (PV) calcium binding proteins in STT neurons after induction of experimental arthritis. This suggests that change in CBP expression could have a significant effect on calcium homeostasis and possibly modulation of synaptic activity in STT neurons., D. Sojka, G. Zacharova, D. Spicarova, J. Palecek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4533. Changes of corneal optical properties after UVB irradiation investigated spectrophotometrically
- Creator:
- Čestmír Čejka, Jan Pláteník, Širc, J., Taras Ardan, Michálek, J., Blanka Brůnová, and Jitka Čejková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, corneal hydration, corneal light absorption, absorption coefficients, UVB rays, 14, and 612
- Language:
- English
- Description:
- Ozone depletion leads to an increase in UV rays of solar radiation reaching the surface of the Earth which is harmful to biological systems. Of the eye, the cornea is directly open to increased amount of UV rays of which mainly UVB rays are capable to induce reactive oxygen species damaging the cells. Previous studies showed that the irradiation of the cornea with UVB rays leads to morphological as well as metabolic disturbances of the cornea. Also, corneal hydration and corneal light absorption are increased after UVB rays. These changes were observed after five days of repeated irradiation of the cornea with UVB rays. The aim of the present paper was to examine how early the changes of corneal hydration and light absorption occur after UVB irradiation. The rabbit corneas were irradiated with UVB rays for one, two, three or four days. Corneal light absorption was examined spectrophotometrically and corneal hydration measured by pachymeter (as corneal thickness). Results show that changes of corneal hydration and light absorption appear early after UVB irradiation and increase along with the number of irradiations. In conclusion, irradiation of the rabbit cornea with UVB rays leads to harmful changes of its optical properties., Č. Čejka ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4534. Changes of cortical perfusion in the early phase of subarachnoid bleeding in a rat model and the role of intracranial hypertension
- Creator:
- Kolar, M., Nohejlova, K., Duska, F., Mares, J., and Pachl, J.
- Type:
- article, model:article, and TEXT
- Subject:
- subarachnoid hemorrhage, decompressive craniectomy, early brain injury, laser speckle-contrast analysis, and rat
- Language:
- English
- Description:
- Brain perfusion is reduced early after subarachnoid hemorrhage (SAH) due to intracranial hypertension and early vasospasm. The contribution of these two mechanisms is unknown. By performing a prophylactic decompressive craniectomy (DC) in a rat model of SAH we aimed to study brain perfusion after the component of intracranial hypertension has been eliminated. We used 2x2 factorial design, where rats received either decompressive craniectomy or sham operation followed by injection of 250 μl of blood or normal saline into prechiasmatic cistern. The cortical perfusion has been continually measured by laser speckle-contrast analysis for 30 min. Injection of blood caused a sudden increase of intracranial pressure (ICP) and drop of cerebral perfusion, which returned to baseline within 6 min. DC effectively prevented the rise of ICP, but brain perfusion after SAH was significantly lower and took longer to normalize compared to non-DC animals due to increased cerebral vascular resistance, which lasted throughout 30 min experimental period. Our findings suggest that intracranial hypertension plays dominant role in the very early hypoperfusion after SAH whilst the role of early vasospasm is only minor. Prophylactic DC effectively maintained cerebral perfusion pressure, but worsened cerebral perfusion by increased vascular resistance.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4535. Changes of Dopamine-Beta-Hydroxylase Activity During Ontogenesis in Healthy Subjects and in an Experimental Model (Rats)
- Creator:
- Paclt, I. and Koudelová, J.
- Type:
- article, model:article, and TEXT
- Subject:
- Dopamine-beta-hydroxylase (DBH), Rats, Human, Serum, Developmental changes, and Noradrenergic system
- Language:
- English
- Description:
- In children and adolescents (250 healthy subjects) serum dopamine-beta-hydroxylase (DBH) activity (23.95.2 to 57.117.5 μmol/min/ml) increases with the age between 3-10 years, later it decreases approximately by the age of 10-14 years. At the age of 21 to 60 years DBH level is stable. Our study described decreasing DBH activity in adolescents at the age of 10-14 years in the studied sample of healthy persons. Experimental animals (200 Wistar rats, 5-120 days old) show the same trend of enzymatic activity, similarly as in humans. DBH activity in rats is between 0.850.1 to 2.80.05 μmol/min/ml. This activity is highest in 5-day-old rats; it decreases till the age of 14 days and increases mainly in 14- to 35-day-old animals. Decrease of DBH activity in rats between 35 to 40 days is significant and corresponds to the reduction of DBH activity in adolescent humans (10-14 years). Adult rats (aged 90-120 days) show a stable DBH activity. DBH activity intermediately decreases in 10- to 14-year-old children. This decrease corresponds to the intermediate developmental changes of electrophysiological parameters (decreasing EEG activity in healthy adolescents occurs in 10-14 years old children). Puberty is coupled with intermediate decreasing of DBH activity in man and also in experimental animals in the period of prominent psychological and physiological changes.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4536. Changes of driver dynamics caused by fatigue
- Creator:
- Vysoký, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Driver's fatigue, drowsy driving, fatigue indicators, reaction time, driver as a controller, and steering wheel movements
- Language:
- English
- Description:
- The main purpose of tliis contribution is to find indicators of the drivers’ fatigue based on compensatory movements of the steering wheel. We focus our attention on changes in delays in drivers’ information processing. We examine drivers fatigued by sleep deprivation. To avoid additional disturbances dne to complicated dynamics of car steering, the results of simple one-dimensional tracking was analyzed. Preliminary results support using three variables applicable as fatigue indicators.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4537. Changes of extracellular matrix of rat cornea after exposure to hypoxia
- Creator:
- Gabriela Mahelková, Jiří Korynta, Moravová, A., Jana Novotná, and Richard Vytášek
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, oftalmologie, rohovka, hypoxie, ophthalmology, cornea, hypoxia, metalloproteinase, oxidative damage, nitrotyrosine, 2, and 577
- Language:
- English
- Description:
- The purpose of the study was to check whether hypoxia of corneal tissue increases the collagenolytic activity due to release of reactive oxygen and nitrogen species. Rats were exposed to hypoxia 10 % O2 for 4, 14, and 21 days. The radical tissue injury was measured by the level of nitrotyrosine and changes in the lipoperoxide-related fluorophores. Collagen protein composition was analyzed by slab gel electrophoresis. The activity of gelatinolytic enzymes was studied using the zymography. The vascularization of the corneas was measured. We found no differences in the corneal tissue in the gel electrophoretic profile of collagenous proteins and gelatinolytic activity between normoxic and hypoxic rats. We did not find any sign of radical tissue injury. There were no changes in the vascularization of corneas after exposition to hypoxia. The environmental 10 % hypoxia does not induce radical tissue injury and an increase of collagenolytic activity in the rat cornea., G. Mahelková, J. Korynta, A. Moravová, J. Novotná, R. Vytášek, J. Wilhelm., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4538. Changes of extracellular space volume and tortuosity in the spinal cord of lewis rats with experimental autoimmune encephalomyelitis
- Creator:
- Šimonová, Z., Svoboda, J., Orkand, P., Bernard, C. C. A., Lassmann, H., and Syková, E.
- Type:
- article, model:article, and TEXT
- Subject:
- astrogliosis, diffusion analysis, oedema, experimental autoimmune encephalomyelitis, and ion-selective microelectrodes
- Language:
- English
- Description:
- Three diffusion parameters of nervous tissue, extracellular space (ECS) volume fraction (λ), tortuosity (α) and non-specific uptake (k’) of tetramethylammonium (TMA + ), were studied in the spinal cord of rats during experimental autoimmune encephalomyelitis (EAE). The three parameters were determined in vivo from concentration-time profiles of TMA+ using ion-selective microelectrodes. EAE was induced by injection of guinea-pig myelin basic protein (MBP), which resulted in typical morphological changes in the CNS tissue, namely inflammatory reaction, astrogliosis, blood-brain barrier (BBB) damage and paralysis. EAE was accompanied by a statistically significant increase of a (mean±S.E.M.) in the dorsal horn from 0.21±0.01 to 0.28±0.02, in the intermediate region from 0.22±0.01 to 0.33±0.02, in the ventral horn from 0.23±0.01 to 0.47±0.02 and in white matter from 0.18±0.03 to 0.30±0.03. There were significant decreases in tortuosity in the dorsal horn and in the intermediate region and decreases in non-specific uptake in the intermediate region and in the ventral horn. Although the inflammatory reaction and the astrogliosis preceded and greatly outlasted the neurological symptoms, the BBB damage had a similar time course. Moreover, there was a close correlation between the changes in extracellular space diffusion parameters and the manifestation of neurological signs. We suggest that the expansion of the extracellular space alters the diffusion properties in the spinal cord. This may affect synaptic as well as non-synaptic transmission, intercellular communication and recovery from acute EAE, and may contribute to the manifestation of neurological signs in EAE rats.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4539. Changes of gastric lipase activity after ethanol and indomethacin administration: influence of pretreatment with allopurinol, pentoxifylline and L-DOPA
- Creator:
- Anna Sedláková, Anton Kohút, and Šarišský, M.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, lipidy, ethanol, lipids, gastric lipase, indomethacin, allopurinol, pentoxifylline, L-DOPA, 14, and 612
- Language:
- English
- Description:
- a1_Gastric lipase (GL) plays an important role in emulsification and digestion of food fat. Lipids are components of the hydrophobic mucus and mucosa barrier. Damage of the gastric mucosa may therefore be related to changes in the lipid content and GL activity. In the present paper, we studied the effect of administration of a single dose of 96 % ethanol (E) and indomethacin 20 mg.kg-1 (IND) on the activity of GL and on the concentrations of nonesterified fatty acids (NEFA) and triacylglycerols (TG) in the gastric mucosa of rats. Furthermore, we studied how these changes are affected by allopurinol (ALO), pentoxifylline (PX) and L-DOPA pretreatment 30 min before administration of E or IND. The effect of sialoadenectomy (SA) on these parameters was also evaluated. We found: 1) significant (p<0.01) inhibition of GL activity after administration of E and IND and also ALO, as well as after pretreatment with ALO before E and PX before IND. L-DOPA administered alone stimulated GL activity, but its administration before IND significantly (p<0.01) inhibited this enzymatic activity. GL activity was decreased to the threshold values in SA rats and after administration of E to SA animals. 2) NEFA concentrations were decreased after E and increased significantly (p<0.01) after IND administration. A marked significant (p<0.01) decrease in NEFA was found after PX and L-DOPA administration. The administration of ALO also lowered the concentration of NEFA. Pretreatment by drugs before E and IND resulted in a significant increase of NEFA in comparison with the drugs given alone (p<0.05 for ALO + E; p<0.01 for PX + IND). 3) TG were also decreased in all experimental groups in comparison with the control group, i.e. after E and IND, after ALO and SA and also after pretreatment by ALO before E. The concentration of TG decreased after PX, significantly (p<0.05) after L-DOPA and after pretreatment by PX before IND., a2_Pretreatment by ALO before E and L-DOPA before IND resulted in the increase of TG in comparison with drugs alone. Thus, these results suggest certain protective effect of pretreatment with ALO, PX and L-DOPA against the E- and IND-induced decrease in NEFA and TG during injury of the gastric mucosa. On the other hand, inhibition of GL activity was also apparent after administration of these drugs before E and IND, which suggest presence of a persisting impairment of lipid digestion in the stomach., A. Sedláková, A. Kohút, M. Šarišský., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4540. Changes of hippocampal neurons after perinatal exposure to ethanol
- Creator:
- Milotová, M., Vladimír Riljak, Kateřina Jandová, Jana Bortelová, Dana Marešová, Jaroslav Pokorný, and Miloš Langmeier
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, ethanol, neurodegenerace, apoptóza, physiology, neurodegeneration, apoptosis, hippocampus, dentate gyrus, 14, and 612
- Language:
- English
- Description:
- The effect of ethanol on the structural development of the central nervous system was studied in offspring of Wistar rats, drinking 20 % ethanol during pregnancy and till the 28th day of their postnatal life. The structural changes in the hippocampus and dentate gyrus were analyzed at the age of 18, 35 and 90 days. A lower width of pyramidal and granular cell layers, cell extinction and fragmentation of numerous nuclei were found in all experimental animals compared to control animals. The extent of neural cell loss was similar in all monitored areas and in all age groups. At the age of 18 and 35 days, the degenerating cells were observed in the CA1 and CA3 area of the hippocampus and in the ventral and dorsal blade of the dentate gyrus. Numerous glial cells replaced the neuronal population of this region. Some degenerating cells with fragmented nuclei were observed at the age of 90 days. Our experiments confirmed the vulnerability of the developing central nervous system by ethanol intake during the perinatal period and revealed a long-lasting degeneration process in the hippocampus and dentate gyrus., M. Milotová, V. Riljak, K. Jandová, J. Bortelová, D. Marešová, K. Pokorný, M. Langmeier., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public