In order to investigate whether covalent histone modifications may be involved in early embryonic reprogramming events, changes in global levels of a series of histone tail modifications were studied during oocyte maturation and pre-implantation mouse development using indirect immunofluorescence and scanning confocal microscopy. Results showed that histone modifications could be classified int...

The role of nitric oxide (NO) in microvascular permeability remains unclear because both increases and decreases in permeability by NO synthase (NOS) inhibitors have been reported. We sought to determine whether blood-borne constituents modify venular permeability responses to the NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). We assessed hydraulic conductivity (L(p)) of pipette-per...

Protein arginine methyltransferases (PRMTs) aid in the regulation of many biological processes by methylating specific arginyl groups within targeted proteins. The varied nature of the response to methylation is, in part, due to the diverse product specificity displayed by the PRMTs. In addition to site location within a protein, biological response is also determined by the degree (mono/dimeth...

The aim of this study was to investigate the influence of nitric oxide (NO) donors (S-nitroso-L-acetyl penicillamine, spermine-NO complex and sodium nitroprusside) and NO synthase inhibitors (N(omega)-nitro-L-arginine methyl ester, N(omega)-nitro-l-arginine, and (+/-)-2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine) on progesterone production by dispersed bovine luteal cells cultured for 24 h. All...

Prof. José M. López-Novoa, Departamento de Fisiología y Farmacología, Facultad de Medicina, Universidad de Salamanca, Avenida Campo Charro s/n, E-37007 Salamanca (Spain) Dear Sir, NO is synthesized from L-arginine [1] in a reaction catalyzed by nitric oxide synthase (NOS) and is oxidized to nitrite and nitrate in a constant ratio, at a constant pH [2]. Nitrite production has been used as an ind...

BACKGROUND l-Arginine is a semi-essential aminoacid with important role in regulation of physiological processes in humans. It serves as precursor for the synthesis of proteins and is also substrate for different enzymes such as nitric oxide synthase. This amino-acid act as free radical scavenger, inhibits the activity of pro-oxidant enzymes and thus acts as an antioxidant and has also bacteric...

Protein methylation is a common posttranslational modification that mostly occurs on arginine and lysine residues. Arginine methylation has been reported to regulate RNA processing, gene transcription, DNA damage repair, protein translocation, and signal transduction. Lysine methylation is best known to regulate histone function and is involved in epigenetic regulation of gene transcription. To...

L-Arginine crosses the cell membrane primarily through the system y(+) transporter. The aim of this study was to investigate the role of L-arginine transport in nitric oxide (NO) production in aortas of rats with heart failure induced by myocardial infarction. Tumor necrosis factor-alpha levels in aortas of rats with heart failure were six times higher than in sham rats (P < 0.01). L-Arginine u...

In this work the enhancing effect of cyclodextrins on the buccal permeation of a hydrophobic model drug, omeprazole was studied. First, the influence of the complexation with cyclodextrins in the absence and in the presence of an alkali agent, L-arginine, on the drug stability was checked at neutral conditions since omeprazole alone is only stable in basic conditions. In vitro transbuccal perme...

We have investigated the effects of L-arginine, D-arginine and L-lysine on airway smooth muscle responsiveness to spasmogens in vitro. Both L-arginine and D-arginine (100 mM) significantly reduced the contractile potency and maximal contractile response to histamine but not to methacholine or potassium chloride in guinea-pig epithelium-denuded isolated trachea. Similarly, the contractile respon...