ABSTRACT
HClO/ClO-, as one of important reactive oxygen species, is a highly reactive unavoidable by-product generated from normal cell metabolism. In recent years, efficient method for detectiing HClO/ClO- is of great important to research its pathological or physiological function in bio-systems. In this work, we have constructed a fluorescent probe (P-Hc) with ratiometric signal for sensing HClO/ClO- in aqueous solution, physiological saline and different serums based on 2-(benzo[d]thiazol-2-yl)phenol dye. The structure of P-Hc was characterized by NMR and HRMS spectrum. The sensing mechanism has also been verified by 1H NMR spectrum. The P-Hc displays good sensitivity and selectivity for HClO/ClO- with a limit of detection (LOD) of 2.03 × 10-6 M. Furthermore, P-Hc has been applied for sensing HClO/ClO- in physiological saline and different serums. Thus, P-Hc may provide a novel method for ratiometric fluorescent sensing HClO/ClO- in bio-samples.
Subject(s)
Fluorescent Dyes , Hypochlorous Acid , Limit of Detection , Serum Albumin, Bovine , WaterABSTRACT
The aim of this study is to investigate whether systemic 5-hydroxytryptamine (5-HT) can promote long-lasting form of respiratory plasticity in vivo via 5-HT2AR-activated protein kinase C (PKC) mechanism. The frequency and peak amplitude of hypoglossal nerve discharges in anesthetized rats were compared before and after intravenous injections of different treatments, including saline, 5-HT, ketanserin tartrate, or staurosporine. The administration of 5-HT at a systemic bolus imposed an initial ephemeral inhibition subsequently followed by striking facilitation, which demonstrates a biphasic manner of hypoglossal nerve output in anesthetized adult rats. The facilitatory stage conformed to the reinforced hypoglossal activity that lasted for more than 60 min after drug administration. The 5-HT evoked biphasic manner of hypoglossal output and hypoglossal nerve activity LTF (hLTF) were 5-HT2A receptor-dependent and coupled to PKC activation. The initial inhibition of hypoglossal activity was associated with nodose ganglion, and the subsequent facilitation was associated with carotid body. The reactive oxygen species (ROS) formation was triggered in the systemic 5-HT2-dependent hLTF model in vivo. The expressions of immunofluorescent histochemistry provide morphological evidence of a 5-HT/5-HT2A receptor coupled to PKC mechanism. In conclusion, systemic 5-HT challenge contributes to long-lasting form of respiratory plasticity and to elicit hLTF or elevated hLTF in animals, which with decreased or even with inhibited peripheral inhibitory activations. The effect of systemic 5-HT was regulated by a 5-HT2AR-activated PKC mechanism.
Subject(s)
Hypoglossal Nerve/drug effects , Respiration/drug effects , Serotonin/pharmacology , Action Potentials/drug effects , Anesthesia, General , Animals , Carotid Body/enzymology , Carotid Body/physiology , Hypoglossal Nerve/physiology , Injections, Intravenous , Ketanserin/pharmacology , Long-Term Potentiation/drug effects , Male , Nerve Tissue Proteins/physiology , Nodose Ganglion/enzymology , Nodose Ganglion/physiology , Oxidative Stress/drug effects , Phosphorylation , Protein Isoforms/metabolism , Protein Kinase C/physiology , Protein Processing, Post-Translational , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Receptor, Serotonin, 5-HT2A/physiology , Serotonin/administration & dosage , Serotonin 5-HT2 Receptor Agonists/pharmacology , Serotonin 5-HT2 Receptor Antagonists/pharmacology , Staurosporine/administration & dosage , Staurosporine/pharmacologyABSTRACT
BACKGROUND: It is known that there is a genetic predisposition to OSAHS. Polymorphisms of the 5-hydroxytryptamine (5-HT) 2A/2C receptors (5-HTR 2A/2C) genes and 5-HT transporter (5-HTT) gene may be associated with the pathogenesis of obstructive sleep apnea-hypopnea syndrome (OSAHS). OBJECTIVES: In this study, we aimed to investigate the prevalence of polymorphisms of the 5-HTR 2A/2C genes and the 5-HTT gene in the Chinese Han OSAHS population. METHODS: A total of 226 unrelated subjects of the Chinese Han population, including 121 OSAHS patients and 105 healthy controls, were involved in the study. The A1438G and T102C polymorphisms of the 5-HTR 2A gene, G796C polymorphisms of the 5-HTR 2C gene, and two polymorphisms (gene-linked polymorphic region [LPR] and variable number tandem repeat [VNTR]) of the 5-HTT gene were identified by polymerase chain reaction (PCR)-RFLP. RESULTS: Compared with the control group, the OSAHS group had significantly higher AA genotype and A allele frequencies in the A1438G polymorphisms of the 5-HTR 2A gene, and had significantly higher frequencies of 10/10, 12/10 genotypes and the allele 10 of 5-HTT-VNTR. There were no significant differences between the genotype distribution and allele frequencies of the OSAHS group and the control group regarding the T102C polymorphisms of the 5-HTR 2A gene and the G796C polymorphisms of the 5-HTR 2C gene, the frequencies of the S or L allele and the S/S, S/L or L/L genotypes in 5-HTT-LPR. CONCLUSIONS: The A1438G polymorphism of the 5-HTR 2A gene might be involved in the pathogenesis in OSAHS subjects of the Chinese Han population. Meanwhile, our findings support the argument that 5-HTT polymorphism appears to be associated with susceptibility to OSAHS, because the allele 10 of 5-HTT-VNTR might be a susceptible factor.