The aim was to determine the effects of enhanced availability of branched-chain amino acids (BCAAs; leucine, isoleucine, and valine) on ammonia detoxification to glutamine (GLN) and protein metabolism in two types of skeletal muscle under hyperammonemic conditions. Isolated soleus (SOL, slow-twitch) and extensor digitorum longus (EDL, fast-twitch) muscles from the left leg of white rats were incubated in a medium with 1 mM ammonia (NH3 group), BCAAs at four times the concentration of the controls (BCAA group) or high levels of both ammonia and BCAA (NH3 + BCAA group). The muscles from the right leg were incubated in basal medium and served as paired controls. L-[1-14C]leucine was used to estimate protein synthesis and leucine oxidation, and 3-methylhistidine release was used to evaluate myofibrillar protein breakdown. We observed decreased protein synthesis and glutamate and α-ketoglutarate (α-KG) levels and increased leucine oxidation, GLN levels, and GLN release into medium in muscles in NH3 group. Increased leucine oxidation, release of branched-chain keto acids and GLN into incubation medium, and protein synthesis in EDL were observed in muscles in the BCAA group. The addition of BCAAs to medium eliminated the adverse effects of ammonia on protein synthesis and adjusted the decrease in α-KG found in the NH3 group. We conclude that (i) high levels of ammonia impair protein synthesis, activate BCAA catabolism, enhance GLN synthesis, and decrease glutamate and α-KG levels and (ii) increased BCAA availability enhances GLN release from muscles and attenuates the adverse effects of ammonia on protein synthesis and decrease in α-KG.
- MeSH
- amoniak otrava MeSH
- citrátový cyklus účinky léků MeSH
- glutamin agonisté metabolismus MeSH
- hyperamonemie enzymologie metabolismus patofyziologie MeSH
- jaterní cirhóza etiologie metabolismus MeSH
- kyseliny ketoglutarové metabolismus MeSH
- methylhistidiny metabolismus MeSH
- orgánová specificita MeSH
- osmolární koncentrace MeSH
- oxidace-redukce MeSH
- potkani Wistar MeSH
- proteolýza účinky léků MeSH
- proteosyntéza účinky léků MeSH
- radioizotopy uhlíku MeSH
- svalová vlákna typu I účinky léků enzymologie metabolismus MeSH
- svalová vlákna typu II účinky léků enzymologie metabolismus MeSH
- svalové proteiny genetika metabolismus MeSH
- techniky in vitro MeSH
- větvené aminokyseliny metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Respiratory irritants are substances which can cause inflammation or other adverse reactions in the respiratory system (lungs, nose, mouth, larynx and trachea) after being inhaled. Depending on the type and amount of irritant gas inhaled, victims can experience symptoms ranging from minor respiratory discomfort to acute airway and lung injury and even death. The lungs are susceptible to many airborne irritants. A common response cascade to a variety of irritant gases includes inflammation, edema and epithelial sloughing which, left untreated, can result in scar formation and pulmonary and airway remodeling. There are hundreds of substances that can pollute air and harm lungs. Harmful gases and chemicals are just one type of airborne pollutants that can adversely affect the lungs. Examples of respiratory irritants include, for example, chlorine, amonium, ozone, sulphur dioxide or nitrogen oxides. These substances, their sources of exposure, physical and other properties, and effects on the victim are summarized in this article.
- MeSH
- amoniak otrava toxicita MeSH
- bronchiolitida etiologie MeSH
- chlor otrava toxicita MeSH
- dráždivé látky * otrava škodlivé účinky toxicita MeSH
- inhalační expozice * škodlivé účinky MeSH
- kyselina chlorovodíková otrava toxicita MeSH
- kyselina fluorovodíková otrava toxicita MeSH
- lidé MeSH
- obstrukce dýchacích cest etiologie MeSH
- oxid dusičitý otrava toxicita MeSH
- oxid siřičitý otrava toxicita MeSH
- ozon otrava toxicita MeSH
- plicní fibróza etiologie MeSH
- plicní nemoci * etiologie MeSH
- plyny * škodlivé účinky toxicita MeSH
- popálení inhalací kouře MeSH
- syndrom dechové tísně etiologie MeSH
- zánět etiologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
- MeSH
- amoniak aplikace a dávkování otrava terapeutické užití MeSH
- chlorid rtuťnatý otrava terapeutické užití MeSH
- diabetes mellitus 1. typu MeSH
- ekzém farmakoterapie MeSH
- finanční podpora výzkumu jako téma MeSH
- hypertenze chemicky indukované MeSH
- lidé MeSH
- otrava rtutí etiologie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
2. vyd. 7 s. ; 21 cm
- MeSH
- amoniak škodlivé účinky otrava MeSH
- hygiena práce MeSH
- první pomoc MeSH
- Publikační typ
- příručky MeSH
- Konspekt
- Hygiena. Lidské zdraví
- NLK Obory
- pracovní lékařství
