Spinal Nerve Axotomy: Effects on I In Vivo and HCNs in DRG Neurons.

In vitro experiments performed on dissociated dorsal root ganglion (DRG) neurons suggest the involvement of the hyperpolarization-activated cation current (I) in enhancing neuronal excitability, potentially contributing to neuropathic pain. However, the more confirmative in vivo information about how nerve injury interacts with I is lacking. In this study, I was recorded in vivo using the dynamic single-electrode voltage clamp (dSEVC) technique on L5 DRG neurons of normal rats and those seven days after spinal nerve axotomy (SNA).

ACE inhibitors from : 3D-QSAR modeling, metabolomics, molecular docking and molecular dynamics simulations.

Unlabelled: Inhibition of ACE is considered as one of the main strategies to reduce hypertension. ACE inhibitors derived from () present a novel antihypertensive agent source. This study employed 3D-QSAR pharmacophore, metabolomics, docking-based screening, and molecular dynamics simulations to identify ACE inhibitors from .

Calcium Overload or Underload? The Effects of Doxorubicin on the Calcium Dynamics in Guinea Pig Hearts.

The severe doxorubicin (DOXO) side effect of cardiomyopathy limits it clinical application as an effective anticancer drug. Although Ca overload was postulated as one of the mechanisms for this toxicity, its role was, however, disputable in terms of the contractile dysfunction. In this work, the dynamics of the intracellular Ca signal were optically mapped in a Langendorff guinea pig heart.

Parvalbumin Interneuron Activation-Dependent Adult Hippocampal Neurogenesis Is Required for Treadmill Running to Reverse Schizophrenia-Like Phenotypes.

Physical exercise can alleviate some of the schizophrenia symptoms in patients, the mechanisms, however, are still unclear. To investigate whether the GABAergic interneuron involved in the therapeutic effect of treadmill running on schizophrenia, the parvalbumin (PV)-positive GABAergic interneurons in the dentate gyrus (DG) was specifically activated or abolished and the effects were evaluated. In the MK801-induced schizophrenia-like animal model, we found:(1) Treadmill running rescued the schizophrenia-related behavioral phenotypes, promoted the adult hippocampal neurogenesis, and increased the dendrite number and complexity of newborn neurons.

The effect of acute dissociation on the electrophysiological properties of rat dorsal root ganglion neurons.

The acutely dissociated neurons from the dorsal root ganglia (DRGs) are extensively used. The effects of acute dissociation on the properties of these neurons are, however, not clear. In this study, the action potentials (APs) were recorded from both acutely dissociated and in vivo identified DRG neurons with patch clamp and sharp electrode recording techniques, respectively.

Difference of acute dissociation and 1-day culture on the electrophysiological properties of rat dorsal root ganglion neurons.

The dissociated dorsal root ganglion (DRG) neurons with or without culture were widely used for investigation of their electrophysiological properties. The culture procedures, however, may alter the properties of these neurons and the effects are not clear. In the present study, we recorded the action potentials (AP) and the voltage-gated Na, K, and Ca currents with patch clamp technique and measured the mRNA of Nav1.

Puerarin Enhances Ca2+ Reuptake and Ca2+ Content of Sarcoplasmic Reticulum in Murine Embryonic Stem Cell-Derived Cardiomyocytes via Upregulation of SERCA2a.

Background/aims: The embryonic stem cell-derived cardiomyocytes (ES-CMs) serve as potential sources for cardiac regenerative therapy. However, the immature sarcoplasmic reticulum (SR) function of ES-CMs prevents its application. In this report, we examined the effect of puerarin, an isoflavone compound, on SR function of murine ES-CMs.

A Single-Cell-Type Real-Time PCR Method Based on a Modified Patch-Pipette Cell Harvesting System.

Real-time PCR is a powerful tool for quantifying nucleic acid expression. Real-time PCR is conventionally performed at the tissue level to guarantee an abundance of nucleic acid for detection. The precision and reliability of this method, however, is limited by usually being composed of a mixture of different cell types.

A rabbit pulmonary vein myocyte isolation method based on simultaneous heart and pulmonary vein perfusion.

Myocytes in the pulmonary veins (PV) play a pivotal role in the development of paroxysmal atrial fibrillation (AF). It is therefore important to understand physiological characteristics of these cells. Studies on these cells are, however, markedly impeded by the fact that single PV myocytes are very difficult to obtain due to lack of effective isolation methods.

Effects of puerarin on cardiac differentiation and ventricular specialization of murine embryonic stem cells.

Aims: It is important to screen and identify chemical compounds to improve the efficiency of cardiac differentiation and specialization of embryonic stem (ES) cells. The objective of this study was to investigate the effect of puerarin, a natural phytoestrogen, on the in vitro cardiac differentiation and ventricular specialization of murine ES cells.

Methods: Cardiac differentiation of murine ES cells was performed by embryoid body (EB)-based differentiation method.

Coculture of embryonic ventricular myocytes and mouse embryonic stem cell enhance intercellular signaling by upregulation of connexin43.

Background: Stem cell therapy has been proposed as a potential treatment strategy for ischemic cardiomyopathy in recent years. A variety of stem cells or stem cell-derived cells can potentially be used for transplantation. Despite improved cardiac function after treatment, one of the major problems is the poor integration between host and donor cells which can lead to post-transplantation arrhythmia and poor long-term outcome.

Molecular and functional changes in voltage-gated Na⁺ channels in cardiomyocytes during mouse embryogenesis.

Background: Embryonic cardiomyocytes undergo profound changes in their electrophysiological properties during development. However, the molecular and functional changes in Na⁺ channel during cardiogenesis are not yet fully explained.

Methods And Results: To study the functional changes in the Na⁺ channel during cardiogenesis, Na⁺ currents were recorded in the early (EDS) and late (LDS) developmental stages of cardiomyocytes in embryonic mice.

Effect of hypoxia on hyperpolarization-activated current in mouse dorsal root ganglion neurons.

The properties of hyperpolarization-activated current (I(h)) in mouse dorsal root ganglion (DRG) neurons and the effect of hypoxia on the current have been studied using whole-cell configuration of the patch clamp technique. Under voltage-clamp mode, I(h), blocked by 1 mM extracellular CsCl, was present in 75.5% of mouse DRG neurons.

Mechanisms of depressor effect of norepinephrine injected into subnucleus commissuriu of nucleus solitarius tractus in rabbits.

This experiment aimed to investigate the effect of adrenergic system in the subnucleus commissuriu of nucleus solitrius tractus (CNTS) on renal nerve discharges. Norepinephrine (NE) was microinjected into the CNTS of rabbits and mean arterial blood pressure (MAP) and renal nerve discharges (FRND) were synchronously recorded. The results indicated that (1) microinjection of norepinephine into the CNTS of rabbit could significantly attenuate the frequency of renal nerve discharge, and at the same time decrease markedly the mean arterial pressure.

Different signal molecules involved in the muscarinic modulation of pacemaker current I(f) on the heart of mouse embryo in different developmental stages.

We isolated mouse embryonic cardiomyocytes derived from timed-pregnant females at different periods and used patch-clamp technique to investigate the muscarinic cholinergic modulation of pacemaker current I(f) in different developmental stages. In early development stage (EDS), muscarinic agonist carbachol (CCh) significantly decreased the magnitude of the pacemaker current I(f) but had no effect in late development stage (LDS). Forskolin (a direct adenylate cyclase activator) and IBMX (a non-selective phosphodiesterase inhibitor) increased I(f) in both EDS and LDS cells.

Muscarinic cholinergic regulation of L-type calcium channel in heart of embryonic mice at different developmental stages.

Aim: To investigate the muscarinic regulation of L-type calcium current (I(Ca-L)) during development.

Methods: The whole cell patch-clamp technique was used to record II(Ca-L) in mice embryonic cardiomyocytes at different stages (the early developmental stage, EDS; the intermediate developmental stage, IDS; and the late developmental stage, LDS). Carbachol (CCh) was used to stimulate M-receptor in the embryonic cardiomyocytes of mice.

[Chronic intermittent hypoxia decreases acute hypoxic inhibition of voltage-gated potassium channel in rat pulmonary arterial smooth muscle cells].

For determination the ionic mechanisms of the hypoxic acclimatization at the level of channels, male Spradue-Dawley rats were divided into two groups: control normoxic group and chronic intermittent hypoxic group [O2 concentration: (10 +/-0.5)%, hypoxia 8 h a day]. Using whole cell patch-clamp technique, voltage-gated potassium channel currents (IK(V)) were recorded in freshly isolated pulmonary arterial smooth muscle cells (PASMCs) of rat with acute isolated method.