Nanomaterials or nanoparticles are commonly used in the cosmetics, medicine, and food industries. Many researchers studied the possible side effects of several nanoparticles including aluminum oxide (Al2O3-nps) and zinc oxide nanoparticles (ZnO-nps). Although, there is limited information available on their direct or side effects, especially on the brain, heart, and lung functions. This study aimed to investigate the neurotoxicity, cardiotoxicity, and lung toxicity induced by Al2O3-nps and ZnO-nps or in combination via studying changes in gene expression, alteration in cytokine production, tumor suppressor protein p53, neurotransmitters, oxidative stress, and the histological and morphological changes. Obtained results showed that Al2O3-nps, ZnO-nps and their combination cause an increase in 8-hydroxy-2 ́-deoxyguanosine (8-OHdG), cytokines, p53, oxidative stress, creatine kinase, norepinephrine, acetylcholine (ACh), and lipid profile. Moreover, significant changes in the gene expression of mitochondrial transcription factor-A (mtTFA) and peroxisome proliferator activator receptor-gamma-coactivator-1alpha (PGC-1alpha) were also noted. On the other hand, a significant decrease in the levels of antioxidant enzymes, total antioxidant capacity (TAC), reduced glutathione (GSH), paraoxonase 1 (PON1), neurotransmitters (dopamine - DA, and serotonin - SER), and the activity of acetylcholine esterase (AChE) in the brain, heart, and lung were found. Additionally, these results were confirmed by histological examinations. The present study revealed that the toxic effects were more when these nanoparticle doses are used in combination. Thus, Al2O3-nps and ZnO-nps may behave as neurotoxic, cardiotoxic, and lung toxic, especially upon exposure to rats in combination.

• MeSH
• acetylcholin farmakologie   MeSH
• antioxidancia farmakologie   MeSH
• kovové nanočástice * toxicita   MeSH
• krysa rodu rattus MeSH
• mozek metabolismus   MeSH
• nanočástice * toxicita   MeSH
• oxid hlinitý toxicita   MeSH
• oxid zinečnatý * toxicita   MeSH
• oxidační stres MeSH
• plíce metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Nicotinic receptors (NRs) play an important role in the cholinergic regulation of heart functions, and converging evidence suggests a diverse repertoire of NR subunits in the heart. A recent hypothesis about the plasticity of β NR subunits suggests that β2-subunits and β4-subunits may substitute for each other. In our study, we assessed the hypothetical β-subunit interchangeability in the heart at the level of mRNA. Using two mutant mice strains lacking β2 or β4 NR subunits, we examined the relative expression of NR subunits and other key cholinergic molecules. We investigated the physiology of isolated hearts perfused by Langendorff's method at basal conditions and after cholinergic and/or adrenergic stimulation. Lack of β2 NR subunit was accompanied with decreased relative expression of β4-subunits and α3-subunits. No other cholinergic changes were observed at the level of mRNA, except for increased M3 and decreased M4 muscarinic receptors. Isolated hearts lacking β2 NR subunit showed different dynamics in heart rate response to indirect cholinergic stimulation. In hearts lacking β4 NR subunit, increased levels of β2-subunits were observed together with decreased mRNA for acetylcholine-synthetizing enzyme and M1 and M4 muscarinic receptors. Changes in the expression levels in β4-/- hearts were associated with increased basal heart rate and impaired response to a high dose of acetylcholine upon adrenergic stimulation. In support of the proposed plasticity of cardiac NRs, our results confirmed subunit-dependent compensatory changes to missing cardiac NRs subunits with consequences on isolated heart physiology.NEW & NOTEWORTHY In the present study, we observed an increase in mRNA levels of the β2 NR subunit in β4-/- hearts but not vice versa, thus supporting the hypothesis of β NR subunit plasticity that depends on the specific type of missing β-subunit. This was accompanied with specific cholinergic adaptations. Nevertheless, isolated hearts of β4-/- mice showed increased basal heart rate and a higher sensitivity to a high dose of acetylcholine upon adrenergic stimulation.

• MeSH
• acetylcholin farmakologie   MeSH
• antagonisté muskarinových receptorů farmakologie   MeSH
• atropin farmakologie   MeSH
• cholinesterasové inhibitory farmakologie   MeSH
• hexamethonium farmakologie   MeSH
• isoprenalin farmakologie   MeSH
• myokard metabolismus   MeSH
• myši knockoutované MeSH
• myši MeSH
• neostigmin farmakologie   MeSH
• nikotinové receptory metabolismus   MeSH
• srdce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Recent experimental work has revealed unusual features of the effect of certain drugs on cardiac inwardly rectifying potassium currents, including the constitutively active and acetylcholine-induced components of acetylcholine-sensitive current (IKAch). These unusual features have included alternating susceptibility of the current components to activation and inhibition induced by ethanol or nicotine applied at various concentrations, and significant correlation between the drug effect and the current magnitude measured under drug-free conditions. To explain these complex drug effects, we have developed a new type of quantitative model to offer a possible interpretation of the effect of ethanol and nicotine on the IKAch channels. The model is based on a description of IKAch as a sum of particular currents related to the populations of channels formed by identical assemblies of different α-subunits. Assuming two different channel populations in agreement with the two reported functional IKAch-channels (GIRK1/4 and GIRK4), the model was able to simulate all the above-mentioned characteristic features of drug-channel interactions and also the dispersion of the current measured in different cells. The formulation of our model equations allows the model to be incorporated easily into the existing integrative models of electrical activity of cardiac cells involving quantitative description of IKAch. We suppose that the model could also help make sense of certain observations related to the channels that do not show inward rectification. This new ionic channel model, based on a concept we call population type, may allow for the interpretation of complex interactions of drugs with ionic channels of various types, which cannot be done using the ionic channel models available so far.

• MeSH
• acetylcholin farmakologie   MeSH
• biologické modely MeSH
• časové faktory MeSH
• dovnitř usměrňující draslíkové kanály spřažené s G proteiny metabolismus   MeSH
• ethanol farmakologie   MeSH
• gating iontového kanálu účinky léků   MeSH
• nikotin farmakologie   MeSH
• počítačová simulace MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND AND AIM: Increased homocysteine (Hcy) is associated with coronary artery disease (CAD). Hcy increases reactive oxygen species (ROS) via NADPH oxidases (Nox), reducing acetylcholine-mediated vasorelaxation. We aimed to determine if putative Nox2 inhibitors prevent Hcy-impaired acetylcholine-mediated vasorelaxation. METHODS AND RESULTS: New Zealand White rabbit and wild-type (C57BL/6) and Nox2-/- (NOX) mice aortic rings were mounted in organ baths. Rabbit rings were incubated with either apocynin (10 μM), gp91ds-tat (GP, 1 μM) or PhoxI2 (1 μM) and mice rings GP (1 μM) only. Some rabbit rings were incubated with 3 mM Hcy, before pre-contraction, followed by dose-response relaxation to acetylcholine (ACh; 0.01μM-10μM). In rabbit rings treated with Hcy and GP, O2‾ donor pyrogallol (1 μM) or Akt activator SC79 (1 μM) was added 5 min before ACh. Mice rings were used to compare Nox2 deletion to normal acetylcholine-mediated relaxation. In rabbits, Hcy reduced acetylcholine-mediated relaxation vs. control (p < 0.0001). Treatment + Hcy reduced relaxation compared with treatment alone (p < 0.0001). Pyrogallol and SC79 reversed the response of GP + Hcy (p = 0.0001). In mice, Nox2 deletion reduced acetylcholine-mediated vasorelaxation. Rabbit tissue analysis revealed that Hcy reduced eNOS phosphorylation at Thr495 and increased eNOS phosphorylation at Ser1177; no further alteration at Thr495 was observed with GP. In contrast, GP prevented increased phosphorylation at Ser1177. CONCLUSIONS: Apocynin, GP and PhoxI2 worsens acetylcholine-mediated vascular relaxation in rabbit aorta, which is supported by results from mouse Nox2 deletion data. These inhibitors worsen Hcy-induced vascular dysfunction, suggesting that current putative Nox2 inhibitors might not be useful in treating HHcy.

• MeSH
• acetofenony farmakologie   MeSH
• acetylcholin farmakologie   MeSH
• aorta účinky léků   enzymologie   MeSH
• fosforylace MeSH
• glykoproteiny farmakologie   MeSH
• homocystein farmakologie   MeSH
• inhibitory enzymů farmakologie   MeSH
• králíci MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• NADPH-oxidasa 2 antagonisté a inhibitory   genetika   metabolismus   MeSH
• serin MeSH
• synthasa oxidu dusnatého, typ III metabolismus   MeSH
• techniky in vitro MeSH
• threonin MeSH
• vazodilatace účinky léků   MeSH
• vazodilatancia farmakologie   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND/AIMS: Reduction of renal blood flow (RBF) is commonly thought to be a causative factor of renal dysfunction in congestive heart failure (CHF), but the exact mechanism of the renal hypoperfusion is not clear. Apart from the activation of neurohormonal systems controlling intrarenal vascular tone, the cause might be altered reactivity of the renal vasculature to endogenous vasoactive agents. METHODS: To evaluate the role of this mechanism, we assessed by an ultrasonic transient-time flow probe maximum RBF responses to renal artery infusion of angiotensin II (ANG II), norepinephrine (NE) and acetylcholine (Ach) in healthy male rats and animals with compensated and decompensated CHF. CHF was induced by volume overload achieved by the creation of the aorto-caval fistula (ACF) in Hannover Sprague-Dawley rats. RESULTS: Maximum responses in RBF to ANG II were similar in rats studied five weeks (compensated phase) and 20 weeks (decompensated phase) after ACF creation when compared to sham-operated rats. On the other hand, NE elicited larger maximum decreases in RBF in rats with CHF (five and 20 weeks post-ACF) than in sham-operated controls. We observed greater maximum vasodilatory responses to Ach only in rats with a compensated stage of CHF (five weeks post-ACF). CONCLUSION: Greater renal vasoconstrictor responsiveness to ANG II or reduced renal vasodilatation in response to Ach do not play a decisive role in the development of renal dysfunction in ACF rats with compensated and decompensated CHF. On the other hand, exaggerated renal vascular responsiveness to NE may be here a contributing causative factor, active in either CHF phase.

• MeSH
• acetylcholin farmakologie   MeSH
• angiotensin II farmakologie   MeSH
• arteria renalis účinky léků   patofyziologie   MeSH
• krysa rodu rattus MeSH
• noradrenalin farmakologie   MeSH
• potkani Sprague-Dawley MeSH
• renální oběh fyziologie   MeSH
• srdeční selhání komplikace   MeSH
• vazodilatace účinky léků   MeSH
• vazokonstrikce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Pathophysiological mechanisms underlying the development of renal dysfunction and progression of congestive heart failure (CHF) remain poorly understood. Recent studies have revealed striking differences in the role of epoxyeicosatrienoic acids (EETs), active products of cytochrome P-450-dependent epoxygenase pathway of arachidonic acid, in the progression of aorto-caval fistula (ACF)-induced CHF between hypertensive Ren-2 renin transgenic rats (TGR) and transgene-negative normotensive Hannover Sprague-Dawley (HanSD) controls. Both ACF TGR and ACF HanSD strains exhibited marked intrarenal EETs deficiency and impairment of renal function, and in both strains chronic pharmacologic inhibition of soluble epoxide hydrolase (sEH) (which normally degrades EETs) normalized EETs levels. However, the treatment improved the survival rate and attenuated renal function impairment in ACF TGR only. Here we aimed to establish if the reported improved renal function and attenuation of progression of CHF in ACF TGR observed after she blockade depends on increased vasodilatory responsiveness of renal resistance arteries to EETs. Therefore, we examined the responses of interlobar arteries from kidneys of ACF TGR and ACF HanSD rats to EET-A, a new stable 14,15-EET analog. We found that the arteries from ACF HanSD kidneys rats exhibited greater vasodilator responses when compared to the ACF TGR arteries. Hence, reduced renal vasodilatory responsiveness cannot be responsible for the lack of beneficial effects of chronic sEH inhibition on the development of renal dysfunction and progression of CHF in ACF HanSD rats.

• MeSH
• acetylcholin farmakologie   MeSH
• hypertenze genetika   patofyziologie   MeSH
• krysa rodu rattus MeSH
• kyselina 8,11,14-eikosatrienová analogy a deriváty   chemie   farmakologie   MeSH
• ledviny krevní zásobení   účinky léků   fyziologie   MeSH
• noradrenalin farmakologie   MeSH
• potkani Sprague-Dawley MeSH
• potkani transgenní MeSH
• progrese nemoci MeSH
• renální oběh účinky léků   fyziologie   MeSH
• renin fyziologie   MeSH
• srdeční selhání genetika   patofyziologie   MeSH
• vazodilatace účinky léků   fyziologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Clinical and experimental studies indicate that muscarinic acetylcholine receptors are potential pharmacological targets for the treatment of neurological diseases. Although these receptors have been described in human, bovine and rat cerebral microvascular tissue, a subtype functional characterization in mouse brain endothelium is lacking. Here, we show that all muscarinic acetylcholine receptors (M1-M5) are expressed in mouse brain microvascular endothelial cells. The mRNA expression of M2, M3, and M5 correlates with their respective protein abundance, but a mismatch exists for M1 and M4 mRNA versus protein levels. Acetylcholine activates calcium transients in brain endothelium via muscarinic, but not nicotinic, receptors. Moreover, although M1 and M3 are the most abundant receptors, only a small fraction of M1 is present in the plasma membrane and functions in ACh-induced Ca2+ signaling. Bioinformatic analyses performed on eukaryotic muscarinic receptors demonstrate a high degree of conservation of the orthosteric binding site and a great variability of the allosteric site. In line with previous studies, this result indicates muscarinic acetylcholine receptors as potential pharmacological targets in future translational studies. We argue that research on drug development should especially focus on the allosteric binding sites of the M1 and M3 receptors.

• MeSH
• acetylcholin farmakologie   MeSH
• alosterické místo MeSH
• cévní endotel cytologie   metabolismus   MeSH
• endoteliální buňky účinky léků   metabolismus   MeSH
• mikrocévy metabolismus   MeSH
• mozek krevní zásobení   MeSH
• myši inbrední BALB C MeSH
• nikotinové receptory metabolismus   MeSH
• receptory muskarinové chemie   metabolismus   MeSH
• vápníková signalizace účinky léků   MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVE: Cardiovascular disease (CVD) caused by atherosclerosis remains a worldwide burden. Hydrogen sulfide is a promising new therapeutic avenue for the treatment of CVD, however reports show exogenous H2S has both vasodilator and vasoconstrictor effects depending on organ examined, and in vitro studies in animal models which are not resistant to developing atherosclerosis are limited. We sought to determine if rabbit arteries constricted or dilated to hydrogen sulfide. MATERIAL AND METHODS: The aorta, carotid, renal and iliac arteries were harvested from New Zealand White rabbits (n=4) and subjected to a concentration response curve to the fast H2S releaser NaHS. In addition, a bolus dose of NaHS was used to determine if further dilation was achievable after maximum dilation to acetylcholine similar to nitric oxide donors. Further, NaHS was used to determine if H2S could impair homocysteine induced endothelial dysfunction. RESULTS: Blood vessels relaxed poorly to NaHS and contracted at higher doses. A bolus dose of NaHS relaxed then contracted the aorta, however a bolus dose of NaHS after maximal relaxation to acetylcholine caused marked contraction. NaHS did not prevent homocysteine induced vascular dysfunction. CONCLUSION: NaHS at low doses caused minor relaxation of rabbit blood vessels, indicating a possible therapeutic benefit for low dose H2S in the cellular milieu.

• MeSH
• acetylcholin farmakologie   MeSH
• arterie účinky léků   MeSH
• ateroskleróza farmakoterapie   MeSH
• donory oxidu dusnatého farmakologie   MeSH
• homocystein farmakologie   MeSH
• králíci MeSH
• relaxace svalu účinky léků   MeSH
• sulfan farmakologie   MeSH
• sulfidy MeSH
• svalová kontrakce účinky léků   MeSH
• svaly hladké cévní účinky léků   MeSH
• techniky in vitro MeSH
• vazodilatace účinky léků   MeSH
• vazodilatancia farmakologie   MeSH
• vazokonstrikce účinky léků   MeSH
• vazokonstriktory MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Nicotine abuse is associated with variety of diseases including arrhythmias, most often atrial fibrillation (AF). Altered inward rectifier potassium currents including acetylcholine-sensitive current I K(Ach) are known to be related to AF pathogenesis. Since relevant data are missing, we aimed to investigate I K(Ach) changes at clinically relevant concentrations of nicotine. Experiments were performed by the whole cell patch clamp technique at 23 ± 1 °C on isolated rat atrial myocytes. Nicotine was applied at following concentrations: 4, 40 and 400 nM; ethanol at 20 mM (∼0.09%). Nicotine at 40 and 400 nM significantly activated constitutively active component of I K(Ach) with the maximum effect at 40 nM (an increase by ∼100%); similar effect was observed at -110 and -50 mV. Changes at 4 nM nicotine were negligible on average. Coapplication of 40 nM nicotine and 20 mM ethanol (which is also known to activate this current) did not show cumulative effect. In the case of acetylcholine-induced component of I K(Ach), a dual effect of nicotine and its correlation with the current magnitude in control were apparent: the current was increased by nicotine in the cells showing small current in control and vice versa. The effect of 40 and 400 nM nicotine on acetylcholine-induced component of I K(Ach) was significantly different at -110 and -50 mV. We conclude that nicotine at clinically relevant concentrations significantly increased constitutively active component of I K(Ach) and showed a dual effect on its acetylcholine-induced component, similarly as ethanol. Synchronous application of nicotine and ethanol did not cause additive effect.

• MeSH
• acetylcholin farmakologie   MeSH
• časové faktory MeSH
• dovnitř usměrňující draslíkové kanály spřažené s G proteiny agonisté   účinky léků   MeSH
• ethanol toxicita   MeSH
• hodnocení rizik MeSH
• kardiomyocyty účinky léků   metabolismus   MeSH
• membránové potenciály MeSH
• nikotin toxicita   MeSH
• potkani Wistar MeSH
• srdeční arytmie chemicky indukované   metabolismus   MeSH
• srdeční síně účinky léků   metabolismus   MeSH
• techniky in vitro MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Alcohol intoxication tends to induce arrhythmias, most often the atrial fibrillation. To elucidate arrhythmogenic mechanisms related to alcohol consumption, the effect of ethanol on main components of the ionic membrane current is investigated step by step. Considering limited knowledge, we aimed to examine the effect of clinically relevant concentrations of ethanol (0.8-80 mM) on acetylcholine-sensitive inward rectifier potassium current I K(Ach). Experiments were performed by the whole-cell patch clamp technique at 23 ± 1 °C on isolated rat and guinea-pig atrial myocytes, and on expressed human Kir3.1/3.4 channels. Ethanol induced changes of I K(Ach) in the whole range of concentrations applied; the effect was not voltage dependent. The constitutively active component of I K(Ach) was significantly increased by ethanol with the maximum effect (an increase by ∼100 %) between 8 and 20 mM. The changes were comparable in rat and guinea-pig atrial myocytes and also in expressed human Kir3.1/3.4 channels (i.e., structural correlate of I K(Ach)). In the case of the acetylcholine-induced component of I K(Ach), a dual ethanol effect was apparent with a striking heterogeneity of changes in individual cells. The effect correlated with the current magnitude in control: the current was increased by eth-anol in the cells showing small current in control and vice versa. The average effect peaked at 20 mM ethanol (an increase of the current by ∼20 %). Observed changes of action potential duration agreed well with the voltage clamp data. Ethanol significantly affected both components of I K(Ach) even in concentrations corresponding to light alcohol consumption.

• MeSH
• acetylcholin farmakologie   MeSH
• akční potenciály MeSH
• CHO buňky MeSH
• Cricetulus MeSH
• dovnitř usměrňující draslíkové kanály spřažené s G proteiny účinky léků   genetika   metabolismus   MeSH
• ethanol toxicita   MeSH
• hodnocení rizik MeSH
• kardiomyocyty účinky léků   metabolismus   MeSH
• kinetika MeSH
• lidé MeSH
• modely kardiovaskulární MeSH
• morčata MeSH
• počítačová simulace MeSH
• potkani Wistar MeSH
• srdeční arytmie chemicky indukované   metabolismus   patofyziologie   MeSH
• srdeční frekvence účinky léků   MeSH
• srdeční síně účinky léků   metabolismus   patofyziologie   MeSH
• transfekce MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• morčata MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH