Long Chaoliang

Bio: Long Chaoliang is an academic researcher. The author has contributed to research in topics: ATP-sensitive potassium channel & Endothelium. The author has an hindex of 3, co-authored 8 publications receiving 66 citations.

Targeting hypertension with a new adenosine triphosphate-sensitive potassium channel opener iptakalim.

Abstract: Hypertension is the most common cardiovascular disease. The discovery of the antihypertensive action of adenosine triphosphate-sensitive potassium (K(ATP)) channel openers was a significant advance in the treatment of hypertension. Iptakalim is a novel K(ATP) channel opener with a unique chemical structure that differs from other K(ATP) openers. Among the 3 different subtypes of K(ATP) channels heterologously expressed in human embryonic kidney cells and Xenopus oocytes, iptakalim exhibits significant selectivity for SUR2B/Kir6.1 channels, mild effects on SUR2A/Kir6.2 channels, and fails to open SUR1/Kir6.2 channels. Iptakalim is a more potent activator of the SUR2B/Kir6.1 subtype of K(ATP) channels than diazoxide and pinacidil, the 2 most commonly studied K(ATP) channel openers. Iptakalim selectively produces arteriolar vasodilation with essentially no effect on the capacitance vessels. It can preferentially relax arterioles and small arteries, without affecting large arteries. Furthermore, iptakalim strongly lowers the blood pressure of hypertensive rodents and humans but has little effect on normotensive rodents and humans. Selective antihypertensive action is not observed with pinacidil or diazoxide and may be due to the high selectivity of iptakalim for the SUR2B/Kir6.1 subtype of K(ATP) channels, as well as its selective relaxation of resistance vessels. In pulmonary arterial smooth muscle cells, iptakalim inhibits the increase of cytoplasmic free Ca2+ concentration, as well as cell proliferation induced by endothelin-1. Furthermore, iptakalim has exerted protective effects against hypertensive damage to target organs in rats and improves endothelial dysfunction associated with cardiovascular diseases by selective activation of the SUR2B/Kir6.1 subtype of K(ATP) channels expressed in the endothelium. Clinical trials of iptakalim in the treatment of mild-moderate hypertension have been completed in China. In additional to strong antihypertensive efficacy, iptakalim seems to have a favorable safety and tolerability profile. Iptakalim is a promising new generation antihypertensive drug.

Activation of SUR2B/Kir6.1 subtype of adenosine triphosphate-sensitive potassium channel improves pressure overload-induced cardiac remodeling via protecting endothelial function.

Abstract: We sought to explore new strategies targeting SUR2B/Kir6.1, a subtype of adenosine triphosphate (ATP)-sensitive potassium channels (KATP), against pressure overload-induced heart failure. The effects of natakalim, a SUR2B/Kir6.1 selective channel opener, on progression of cardiac remodeling were investigated. Pressure overload-induced heart failure was induced in Wistar rats by abdominal aortic banding. The effects of natakalim (1, 3, and 9 mg·kg⁻¹·d⁻¹ for 10 weeks) on myocardial hypertrophy and heart failure, cardiac histology, vasoactive compounds, and gene expression were assessed. Ten weeks after the onset of pressure overload, natakalim treatment potently inhibited cardiac hypertrophy and prevented heart failure. Natakalim remarkably inhibited the changes of left ventricular hemodynamic parameters and reversed the increase of heart mass index, left ventricular weight index, and lung weight index. Histological examination demonstrated that there was no significant hypertrophy or fibrosis in pressure-overloaded hearts of natakalim-treated rats. Ultrastructural examination of hearts revealed well-organized myofibrils with mitochondria grouped along the periphery of longitudinally oriented fibers in rats from the natakalim group. The content of serum nitric oxide and plasma prostacyclin was increased, whereas that of plasma endothelin-1 and cardiac tissue hydroxyproline and atrial and B-type natriuretic peptide messenger RNA was downregulated in natakalim-treated rats. Natakalim at 0.01-100 µM had no effects on isolated working hearts derived from Wistar rats; however, natakalim had endothelium-dependent vasodilatory effects on the isolated tail artery helical strips precontracted with norepinephrine. These results indicate that natakalim reduces heart failure caused by pressure overloading by activating the SUR2B/Kir6.1 KATP channel subtype and protecting against endothelial dysfunction.

Natakalim Ameliorates Isoproterenol-Induced Chronic Heart Failure by Protecting against Endothelial Dysfunction.

Abstract: The pharmacological effects and underlying mechanisms of natakalim, a novel SUR2B/Kir6.1-KATP channel opener, against chronic heart failure induced by isoproterenol in rats were investigated. Male Wistar rats were administered isoproterenol subcutaneously (85 mg/kg, 7 days) to induce chronic heart failure and were then treated with natakalim or saline for 6 weeks. Their blood pressure, heart rates and cardiac functions were measured using an 8-channel physiological recorder. Sophisticated technologies such as histological analysis, ELISA, radioimmunoassay, immunohistochemistry, real-time PCR and western blotting were employed for analysis. Natakalim (1, 3, 9 mg/kg/day, orally) or saline was administered for 6 weeks orally via a gastric tube to rats that had been injected with isoproterenol. Natakalim remarkably inhibited changes in left ventricular hemodynamic parameters and decreased the heart mass index, the left ventricular weight index, right ventricular weight index and lung weight index. Histological examination demonstrated no significant hypertrophy or fibrosis in the hearts of the natakalim-treated rats. Mechanistically, natakalim attenuates the elevation of plasma nitric oxide (NO) level and inducible NO synthase in cardiac tissue induced by isoproterenol. Additionally, natakalim inhibits the endothelin signaling system by decreasing both the content of endothelin-1 in the plasma and the protein levels of cardiac endothelin receptors A and B. Moreover, natakalim could augment the plasma prostacyclin concentration. In conclusion, our study provides evidence that natakalim effectively ameliorates isoproterenol-induced chronic heart failure in rats by protecting against endothelial dysfunction.

Dynamic-change synchronic measurement and recording device for small animal oxygen consumption

Abstract: The utility model discloses a dynamic-change synchronic measurement and recording device for small animal oxygen consumption The dynamic-change synchronic measurement and recording device comprises an animal cabin, an absorbent bottle is arranged in the animal cabin, an upper opening of the animal cabin is connected with a first water detection meter, two electrodes of the first water detection meter are connected with a control system of a first relay, two ends of the control system of the first relay are respectively connected with a pure oxygen storage bottle and the animal cabin through rubber pipes, an upper opening of the pure oxygen storage bottle is connected wit a second water detection meter, two electrodes of the second water detection meter are connected with a control system of a second relay, two ends of the control system of the second relay are respectively connected with the pure oxygen storage bottle and a water storage bottle through rubber pipes, the water storage bottle is arranged on a balance, and the balance is connected with a computer through a data output line The dynamic-change synchronic measurement and recording device for small animal oxygen consumption is a set of gas-liquid linkage and real time recording device, has the advantages of multiple in channels, capable of automatically recording in real time and accurate in data record, can be used for automatically and continuously measuring and recording whole animal oxygen consumption and oxygen consumption speed of various models, and is simple, convenient, efficient and accurate to test

KATP Channels in the Cardiovascular System.

Abstract: KATP channels are integral to the functions of many cells and tissues. The use of electrophysiological methods has allowed for a detailed characterization of KATP channels in terms of their biophysical properties, nucleotide sensitivities, and modification by pharmacological compounds. However, even though they were first described almost 25 years ago (Noma 1983, Trube and Hescheler 1984), the physiological and pathophysiological roles of these channels, and their regulation by complex biological systems, are only now emerging for many tissues. Even in tissues where their roles have been best defined, there are still many unanswered questions. This review aims to summarize the properties, molecular composition, and pharmacology of KATP channels in various cardiovascular components (atria, specialized conduction system, ventricles, smooth muscle, endothelium, and mitochondria). We will summarize the lessons learned from available genetic mouse models and address the known roles of KATP channels in cardiovascular pathologies and how genetic variation in KATP channel genes contribute to human disease.

Signaling pathways for the vascular effects of hydrogen sulfide.

Abstract: Purpose of reviewThe physiological and pathophysiological importance of endogenous hydrogen sulfide to cardiovascular health has been recognized in recent years. The signaling mechanisms underlying the multifaceted vascular effects of H2S, on the contrary, have been unclear. This article reviews rec

Endothelial dysfunction in pulmonary arterial hypertension: an evolving landscape (2017 Grover Conference Series):

Abstract: Endothelial dysfunction is a major player in the development and progression of vascular pathology in pulmonary arterial hypertension (PAH), a disease associated with small vessel loss and obstructive vasculopathy that leads to increased pulmonary vascular resistance, subsequent right heart failure, and premature death. Over the past ten years, there has been tremendous progress in our understanding of pulmonary endothelial biology as it pertains to the genetic and molecular mechanisms that orchestrate the endothelial response to direct or indirect injury, and how their dysregulation can contribute to the pathogenesis of PAH. As one of the major topics included in the 2017 Grover Conference Series, discussion centered on recent developments in four areas of pulmonary endothelial biology: (1) angiogenesis; (2) endothelial-mesenchymal transition (EndMT); (3) epigenetics; and (4) biology of voltage-gated ion channels. The present review will summarize the content of these discussions and provide a perspective on the most promising aspects of endothelial dysfunction that may be amenable for therapeutic development.

Potassium Channels: Structures, Diseases, and Modulators

Abstract: Potassium channels participate in many critical biological functions and play important roles in a variety of diseases. In recent years, many significant discoveries have been made which motivate us to review these achievements. The focus of our review is mainly on three aspects. Firstly, we try to summarize the latest developments in structure determinants and regulation mechanism of all types of potassium channels. Secondly, we review some diseases induced by or related to these channels. Thirdly, both qualitative and quantitative approaches are utilized to analyze structural features of modulators of potassium channels. Our analyses further prove that modulators possess some certain natural-product scaffolds. And pharmacokinetic parameters are important properties for organic molecules. Besides, with in silico methods, some features that can be used to differentiate modulators are derived. There is no doubt that all these studies on potassium channels as possible pharmaceutical targets will facilitate future translational research. All the strategies developed in this review could be extended to studies on other ion channels and proteins as well.