Acetaldehyde ; pharmacology ; Animals ; Cells, Cultured ; Extracellular Signal-Regulated MAP Kinases ; antagonists & inhibitors ; Flavonoids ; pharmacology ; Hepatocytes ; cytology ; physiology ; Rats

OBJECTIVETo investigate the effect of PD98059 on the proliferation and cell cycle of rat hepatic stellate cells (HSCs) stimulated by acetaldehyde and explore its mechanism.

METHODSRat HSCs stimulated by acetaldehyde were incubated with different concentrations of PD98059. Cell proliferation was assessed by MTT colorimetric assay. Cell cycle was analysed by flow cytometry. The mRNA of cyclin D1 and CDK4 were examined by RT-PCR.

RESULTS20, 50, 100 micromol/L PD98059 could significantly inhibit the proliferation of HSCs stimulated by acetaldehyde in a does-dependent manner (0.109+/-0.020, 0.081+/-0.010 and 0.056+/-0.020 vs 0.146+/-0.030, F=31.385, P<0.05) and provoke G0/G1 phase arrest of HSCs stimulated by acetaldehyde in a does-dependent manner (61.9%+/-6.3%, 64.1%+/-3.3% and 70.9%+/-4.8% vs 55.2%+/-4.4%, F=16.402, P<0.05). 50, 100 micromol/L PD98059 could markedly inhibit cyclin D1 mRNA expression of HSC stimulated by acetaldehyde (0.56+/-0.04 and 0.46+/-0.03 vs 0.65+/-0.07, F=68.758, P<0.05) and CDK4 mRNA expression (0.39+/-0.07 and 0.33+/-0.05 vs 0.50+/-0.06, F=29.406, P<0.05).

CONCLUSIONThe Erk signal transduction pathway plays an important role in regulating the proliferation and cell cycle of rat hepatic stellate cells stimulated by acetaldehyde, which may be partly related to its regulative effect on the expression of cyclin D1 gene and CDK4 gene

Acetaldehyde ; pharmacology ; Animals ; Cells, Cultured ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 4 ; Cyclin-Dependent Kinases ; metabolism ; Enzyme Inhibitors ; pharmacology ; Flavonoids ; pharmacology ; Hepatocytes ; drug effects ; Proto-Oncogene Proteins ; Rats

Acetaldehyde ; pharmacology ; Animals ; Cell Division ; drug effects ; Cells, Cultured ; Collagen ; biosynthesis ; Drug Interactions ; Drugs, Chinese Herbal ; pharmacology ; Hepatocytes ; cytology ; drug effects ; Rats

Ethanol has various effects on male sexual activity under the influence of direct and indirect, in acute and chronic alcohol ingestion. However, whether acetaldehyde, a principal metabolite of ethanol, may affect penile erection directly has still not been elucidated. This present study was, therefore, designed to clarify the pharmacologic effects of the acetaldehyde on corpus cavernosal smooth muscle. Corpus cavernosal strips were prepared from rabbit penises. Isometric tension changes of rabbit corpus cavernosal strips to various drugs and electrical field stimulation (EFS) in an organ chamber were recorded with a pressure transducer after active muscle tone had been induced by phenylephrine (10(-5) mol/L). At the concentrations employed, acetaldehyde had no effect on the pH of the bathing medium. Acetaldehyde in each concentration did not significantly affect resting tone of the smooth muscle during 30 min incubation. Acetaldehyde suppressed contractility induced by phenylephrine and KCI at 10(-4) mol/L, and relaxation induced by EFS and bethanechol at 10(-3) mol/L and 10(-4) mol/L respectively, but acetaldehyde enhanced relaxation induced by ATP at high acetaldehyde level. Sodium nitroprusside-induced relaxation was not affected at any employed acetaldehyde concentration. This suggests that increasing the acetaldehyde level may contribute to male erectile dysfunction mainly by the inhibition of nitric oxide formation.
Acetaldehyde/pharmacology* ; Animal ; Bethanechol/pharmacology ; In Vitro ; Male ; Muscle Contraction/drug effects ; Muscle Relaxation/drug effects ; Muscle, Smooth/physiology ; Muscle, Smooth/drug effects* ; Nitroprusside/pharmacology ; Penis/physiology ; Penis/drug effects* ; Phenylephrine/pharmacology ; Potassium Chloride/pharmacology ; Rabbits

Ethanol has various effects on male sexual activity under the influence of direct and indirect, in acute and chronic alcohol ingestion. However, whether acetaldehyde, a principal metabolite of ethanol, may affect penile erection directly has still not been elucidated. This present study was, therefore, designed to clarify the pharmacologic effects of the acetaldehyde on corpus cavernosal smooth muscle. Corpus cavernosal strips were prepared from rabbit penises. Isometric tension changes of rabbit corpus cavernosal strips to various drugs and electrical field stimulation (EFS) in an organ chamber were recorded with a pressure transducer after active muscle tone had been induced by phenylephrine (10(-5) mol/L). At the concentrations employed, acetaldehyde had no effect on the pH of the bathing medium. Acetaldehyde in each concentration did not significantly affect resting tone of the smooth muscle during 30 min incubation. Acetaldehyde suppressed contractility induced by phenylephrine and KCI at 10(-4) mol/L, and relaxation induced by EFS and bethanechol at 10(-3) mol/L and 10(-4) mol/L respectively, but acetaldehyde enhanced relaxation induced by ATP at high acetaldehyde level. Sodium nitroprusside-induced relaxation was not affected at any employed acetaldehyde concentration. This suggests that increasing the acetaldehyde level may contribute to male erectile dysfunction mainly by the inhibition of nitric oxide formation.
Acetaldehyde/pharmacology* ; Animal ; Bethanechol/pharmacology ; In Vitro ; Male ; Muscle Contraction/drug effects ; Muscle Relaxation/drug effects ; Muscle, Smooth/physiology ; Muscle, Smooth/drug effects* ; Nitroprusside/pharmacology ; Penis/physiology ; Penis/drug effects* ; Phenylephrine/pharmacology ; Potassium Chloride/pharmacology ; Rabbits

OBJECTIVETo identify the effect of ethanol and its metabolite acetaldehyde on acetylcholine-sensitive K(+) channel Kir3.1 protein expression, and explore the potential role of this channel and acetaldehyde in arrhythmia caused by acute alcoholic intoxication.

METHODSPrimary atrial cardiomyocytes were isolated from 150 newborn SD rats by typsin and type II collagenase, cultured and troponin I was determined by immunofluorescence. Cell survival in 200-800 mmol/L ethanol or 50-500 µmol/L acetaldehyde treated cells for 24 hours was measured by CCK-8 assay to determine the concentration of ethanol and acetaldehyde for inducing apoptosis in cardiomyocytes. The highest non-apoptotic concentration (200 mmol/L) of ethanol and acetaldehyde (100 µmol/L) was used in the main study. Kir3.1 protein expression was detected by Western blot.

RESULTS(1) Cellular immunofluorescence results showed that cultured cells are cardiomyocytes, and more than 90% of these cells are troponin I positive. (2) CCK-8 assay demonstrated that the survival rate of cardiomyocytes in the groups treated by ethanol over 400 mmol/L for 24 hours or acetaldehyde over 400 µmol/L was significantly lower than that of the control group (P < 0.05), while the survival rate was similar in cardiomyocytes treated by ethanol less than 200 mmol/L or acetaldehyde less than 350 µmol/L for 24 hours and the control group (P > 0.05). (3) Western-bolt assay revealed that ethanol and acetaldehyde treatment for 24 hours upregulated Kir3.1 protein expression in primary atrial cardiomyocytes of newborn SD rats by (44.52 ± 23.07)% and (45.04 ± 22.01)% respectively compared with the control group (all P < 0.01).

CONCLUSIONSAcute ethanol and acetaldehyde treatment could significantly upregulate the protein expression of acetylcholine-sensitive K(+) channel Kir3.1, this might serve as a potential mechanism for arrhythmia caused by acute alcoholic intoxication.

Acetaldehyde ; metabolism ; Acetylcholine ; Alcoholic Intoxication ; metabolism ; Animals ; Apoptosis ; Cells, Cultured ; Ethanol ; pharmacology ; G Protein-Coupled Inwardly-Rectifying Potassium Channels ; drug effects ; Heart Atria ; Myocytes, Cardiac ; drug effects ; Rats ; Rats, Sprague-Dawley ; Sincalide

Acetaldehyde ; pharmacology ; Animals ; Anthracenes ; pharmacology ; Apoptosis ; drug effects ; Cell Line ; Cell Proliferation ; drug effects ; Collagen ; biosynthesis ; Collagen Type I ; biosynthesis ; Collagen Type III ; biosynthesis ; Flow Cytometry ; Hepatic Stellate Cells ; drug effects ; metabolism ; JNK Mitogen-Activated Protein Kinases ; antagonists & inhibitors ; Liver Cirrhosis, Alcoholic ; pathology ; prevention & control ; Rats ; Signal Transduction ; drug effects