[Effects of Rho/ROCK signal pathway on AGEs-induced morphological and functional changes in human dermal microvascular endothelial cells.].

The present study aimed to determine the role of Rho/Rho kinase (Rho/ROCK) phosphorylation on advanced glycation end products (AGEs)-induced morphological and functional changes in human dermal microvascular endothelial cells (HMVECs). HMVECs were respectively incubated with different concentrations of AGEs-modified human serum albumin (AGEs-HSA) for different time. In some other cases, HMVECs were pretreated with ROCK inhibitors (H-1152 or Y-27632).

Calcium mobilization is required for peroxynitrite-mediated enhancement of spontaneous transient outward currents in arteriolar smooth muscle cells.

Transiently local release of Ca(2+) from the sarcoplasmic reticulum (SR) activates nearby Ca(2+)-activated K(+) channels to produce spontaneous transient outward currents (STOCs) in smooth muscle cells. The purpose of the present study was to investigate the possible effect of peroxynitrite (ONOO(-)) on STOCs in mesenteric arteriolar smooth muscle cells (ASMCs) and decide whether Ca(2+) mobilization was involved in STOCs alteration by ONOO(-). STOCs were recorded and characterized using the perforated whole-cell patch-clamp configuration.

Effects of lipopolysaccharide on actin reorganization and actin pools in endothelial cells.

Objective: To investigate the dose and time-dependent effects of lipopolysaccharide (LPS) on cytoskeletal F-acitn and G-actin reorganizations by visualizing their distribution and measuring their contents in human umbilical vein endothelial cell line ECV-304.

Methods: F-actin was labeled with rhodamine-phalloidin and G-actin with deoxyribonuclease I (DNase I)conjugated with fluorescein isothiocyanate (FITC). Contents of cytoskeletal proteins were obtained by flow cytometry.

Myosin light-chain kinase contributes to short-term endothelial cell cytoskeletal alteration induced by serum from burned rats.

Objectives: To investigate the time-dependent effects of serum from burned rats on cytoskeletal filamentous actin (F-actin) reorganization by visualizing their distribution in human umbilical vein endothelial cell line ECV-304 and evaluate the role of myosin light-chain kinase (MLCK) in this process.

Methods: The serum-starved ECV-304 cells were incubated with the serum from burned rats for 30 min, 1, 2, 4, and 6 h, respectively, and 30 min before or after the incubation, the cells were treated with 5 micromol/L ML-7 for 30 min. F-actin was stained with rhodamine-phalloidin and observed under fluorescence microscope.

Mobilization of intracellular calcium by peroxynitrite in arteriolar smooth muscle cells from rats.

The present study was designed to investigate the possible effects of peroxynitrite (ONOO(-)) on the intracellular calcium concentration ([Ca(2+)](i)) of mesenteric arteriolar smooth muscle cells (ASMCs), and to reveal the underlying mechanisms by using fluorescence imaging analysis. The results showed that ONOO(-) could exert a concentration- and time-dependent but also a dual effect on [Ca(2+)](i). Bolus administration with a low concentration of ONOO(-) (25 microM) decreased [Ca(2+)](i), whereas higher concentrations (50 or 100 microM) increased [Ca(2+)](i) persistently.

Effect of SOD and NaHCO3 on the vascular hyporeactivity of rats after severe hemorrhagic shock.

Objective: To investigate the effect of SOD and NaHCO3 on the vascular hyporeactivity after severe hemorrhagic shock in rats.

Methods: Twenty eight Sprague-Dawley rats were divided randomly into 4 groups of 7 each: SOD-treated group, NaHCO3-treated group, SOD+NaHCO3-treated group and normal saline-treated control group. The responses of arterioles to norepinephrine (NE), the effects of dopamine on blood pressure, blood flow velocity in arterioles, the mean arterial pressure (MAP), and the survival time within 24 h were measured.

Peroxynitrite induces arteriolar smooth muscle cells membrane hyperpolarization with arteriolar hyporeactivity in rats.

Peroxynitrite (ONOO-) has been recently known to act as a potent cytotoxin during pathogenesis of various diseases. This study aimed to investigate the possible effect of ONOO- on the cremaster muscle arteriolar reactivity in response to noradrenaline and subsequently determined whether membrane hyperpolarization and potassium channel activation were involved in ONOO(-)-induced alteration of arteriolar reactivity. The results demonstrated that 1) ONOO- could decrease arteriolar reactivity in a time- and concentration-dependent manner with no significant alteration of arteriolar diameter; 2) Superfusion with 20 microM ONOO- over 40 minutes showed slight but not significant influence on the resting potential (Em) of arteriolar smooth muscle cells (ASMCs).

[Properties of large-conductance calcium-activated potassium channel in rat mesenteric arteriole smooth muscle cells].

Objective: To investigate the electrophysiological properties of large-conductance calcium-activated potassium channel (BKCa) in mesenteric arteriole smooth muscle cells of rat.

Method: Mesenteric arteriolar smooth muscle cells from rats were isolated and inside-out patch clamp technique was used to study BKCa.

Results: The single channel conductance of BKCa recorded was 221+/-6 pS and the reversal potential was -0.

[Effect of protein kinase on endothelial cytoskeleton induced by septic shock].

Objective: To study the effect of cGMP-dependent protein kinase (PKG) on the pathogenesis of septic shock.

Methods: Confluent endothelial cells were disintegrated and centrifugated to obtain cell lysates after being treated with LPS or PKG activator 8-Br-cGMP. PKG activity of lysates was measured with radioactive isotope label method in a reaction system of phosphorylation of specific substrate H2B by PKG, and the shape and the distribution of intracellular filamentous actin were detected by specific fluorescence staining.

[Effects of aging and hypoxia on the proliferation of cultured rat pulmonary arterial smooth muscle cells].

Objective: To study the effects of aging and hypoxia on the proliferative behavior of cultured pulmonary arterial smooth muscle cells (PASMCs).

Methods: PASMCs isolated from aged (18-24 months) and young (3-4 months) rats were divided, according to the different treatments the cells were subjected to, into young and aged normoxic groups (groups A and B) and young and aged hypoxic groups (groups C and D) respectively. MTT cell proliferation assay, 3H-TdR incorporation assay, flow cytometriy and immunocytochemical analysis were respectively employed to observe the proliferative behavior.

Dynamic changes in serum level of nitric oxide and its mechanisms in rats with traumatic shock.

Objective: To investigate the dynamic changes of serum nitric oxide (NO) level and its mechanisms in rats in traumatic shock.

Methods: Rat models of traumatic shock were established by fracturing the posterior limb of the rats. Serum levels of nitrate/nitrite were measured with the method described by Griess.