OBJECTIVETo investigate whether the methanol extract of Berberis amurensis Rupr. (BAR) augments penile erection using in vitro and in vivo experiments.

METHODSThe ex vivo study used corpus cavernosum strips prepared from adult male New Zealand White rabbits. In in vivo studies for intracavernous pressure (ICP), blood pressure, mean arterial pressure (MAP), and increase of peak ICP were continuously monitored during electrical stimulation of Sprague-Dawley rats.

RESULTSPreconstricted with phenylephrine (PE) in isolated endotheliumintact rabbit corus cavernosum, BAR relaxed penile smooth muscle in a dose-dependent manner, which was inhibited by pretreatment with NG-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, and H-[1,2,4]-oxadiazole-[4,3-α]-quinoxalin-1-one, a soluble guanylyl cclase inhibitor. BAR significantly relaxed penile smooth muscles dose-dependently in ex vivo, and this was inhibited by pretreatment with L-NAME H-[1,2,4]-oxadiazole-[4,3-α]-quinoxalin-1-one. BAR-induced relaxation was significantly attenuated by pretreatment with tetraethylammonium (TEA, P<0.01), a nonselective K channel blocker, 4-aminopyridine (4-AP, P<0.01), a voltage-dependent K channel blocker, and charybdotoxin (P<0.01), a large and intermediate conductance Ca sensitive-K channel blocker, respectively. BAR induced an increase in peak ICP, ICP/MAP ratio and area under the curve dose dependently.

CONCLUSIONBAR augments penile erection via the nitric oxide/cyclic guanosine monophosphate system and Ca sensitive-K (BK and IK) channels in the corpus cavernosum.

Animals ; Area Under Curve ; Berberis ; chemistry ; Blood Pressure ; drug effects ; Cyclic GMP ; metabolism ; Epoprostenol ; pharmacology ; In Vitro Techniques ; Indomethacin ; pharmacology ; Male ; Models, Biological ; Muscle Relaxation ; drug effects ; Muscle, Smooth ; drug effects ; physiology ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide ; metabolism ; Penile Erection ; drug effects ; Phenylephrine ; pharmacology ; Plant Extracts ; pharmacology ; Potassium Channel Blockers ; pharmacology ; Potassium Channels ; metabolism ; Pressure ; Rabbits

Scutellarin (SCU), a flavonoid from a traditional Chinese medicinal plant. Our previous study has demonstrated that SCU relaxes mouse aortic arteries mainly in an endothelium-depend-ent manner. In the present study, we investigated the vasoprotective effects of SCU against HR-induced endothelial dysfunction (ED) in isolated rat CA and the possible mechanisms involving cyclic guanosine monophosphate (cGMP) dependent protein kinase (PKG). The isolated endothelium-intact and endothelium-denuded rat CA rings were treated with HR injury. Evaluation of endothelium-dependent and -independent vasodilation relaxation of the CA rings were performed using wire myography and the protein expressions were assayed by Western blotting. SCU (10-1 000 μmol·L(-1)) could relax the endothelium-intact CA rings but not endothelium-denuded ones. In the intact CA rings, the PKG inhibitor, Rp-8-Br-cGMPS (PKGI-rp, 4 μmol·L(-1)), significantly blocked SCU (10-1 000 μmol·L(-1))-induced relaxation. The NO synthase (NOS) inhibitor, NO-nitro-L-arginine methylester (L-NAME, 100 μmol·L(-1)), did not significantly change the effects of SCU (10-1 000 μmol·L(-1)). HR treatment significantly impaired ACh-induced relaxation, which was reversed by pre-incubation with SCU (500 μmol·L(-1)), while HR treatment did not altered NTG-induced vasodilation. PKGI-rp (4 μmol·L(-1)) blocked the protective effects of SCU in HR-treated CA rings. Additionally, HR treatment reduced phosphorylated vasodilator-stimulated phosphoprotein (p-VASP, phosphorylated product of PKG), which was reversed by SCU pre-incubation, suggesting that SCU activated PKG phosphorylation against HR injury. SCU induces CA vasodilation in an endothelium-dependent manner to and repairs HR-induced impairment via activation of PKG signaling pathway.
Animals ; Apigenin ; pharmacology ; Cell Adhesion Molecules ; drug effects ; Cell Hypoxia ; Coronary Vessels ; drug effects ; Cyclic GMP ; analogs & derivatives ; metabolism ; pharmacology ; Cyclic GMP-Dependent Protein Kinases ; Glucuronates ; pharmacology ; Microfilament Proteins ; drug effects ; NG-Nitroarginine Methyl Ester ; metabolism ; pharmacology ; Phosphoproteins ; drug effects ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; complications ; physiopathology ; Signal Transduction ; drug effects ; Thionucleotides ; metabolism ; pharmacology ; Vasodilation ; drug effects ; physiology

BACKGROUNDCoronary artery damage from Kawasaki disease (KD) is closely linked to the dysfunction of the endothelial progenitor cells (EPCs). The aim of the present study was to evaluate the modulatory effect of granulocyte colony-stimulating factor (G-CSF) on EPCs and elastin breakdown of coronary arteries in a KD mouse model.

METHODSA Lactobacillus casei cell wall extract (LCWE)-induced KD model was established in C57BL/6 mice that were subsequently administrated with recombinant human G-CSF (rhG-CSF). Nω-nitro-L-arginine methyl ester (L-NAME) was administrated for the negative intervention. Evaluations included coronary artery lesions, EPC number and functions, and the plasma concentration of nitric oxide (NO).

RESULTSElastin breakdown was found in the coronary arteries of model mice 56 days after injection of LCWE. The number of circulating EPCs, plasma concentration of NO, and functions of bone marrow EPCs, including proliferation, adhesion, and migration abilities, were all lower in the KD model group compared with those in the control group. After administration of rhG-CSF, the number of circulating EPCs and plasma concentration of NO were increased significantly compared with those in the KD model group. There were also increases in the functional indexes of EPCs. Furthermore, rhG-CSF administration improved the elastin breakdown effectively. However, these protective effects of rhG-CSF on coronary arteries were attenuated by L-NAME.

CONCLUSIONThe present study indicated that the administration of G-CSF prevents elastin breakdown of the coronary arteries by enhancing the number and functions of EPCs via the NO system, and then accelerates the repair of coronary artery lesions in the KD.

Animals ; Coronary Vessels ; cytology ; drug effects ; metabolism ; Disease Models, Animal ; Elastin ; metabolism ; Endothelial Progenitor Cells ; cytology ; Granulocyte Colony-Stimulating Factor ; therapeutic use ; Male ; Mice ; Mice, Inbred C57BL ; Mucocutaneous Lymph Node Syndrome ; blood ; drug therapy ; metabolism ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitrogen Oxides ; blood

BACKGROUNDPreeclampsia (PE) is a multifactorial pregnancy complication. Maternal underlying condition and adverse factors both influence the pathogenesis of PE. Abnormal lipid metabolism as a maternal underlying disease may participate in the occurrence and development of PE. This study aimed to observe the effects of adverse factors on PE-like symptoms of pregnant mice with genetic abnormal lipid metabolism.

METHODSApolipoprotein C-III (ApoC3) transgenic mice with abnormal lipid metabolism were subcutaneously injected with L-arginine methyl ester (L-NAME) or normal saline (NS) daily starting at Day 7 or 16 of pregnancy (ApoC3+L-NA and ApoC3+NS groups), and wild-type (WT) mice served as a control (WT+L-NA and WT+NS groups). All mice were subdivided into early and late subgroups by injection time. The mean arterial pressure (MAP) and urinary protein were measured. Pregnancy outcomes, including fetal weight, placental weight, live birth rate, and fetal absorption rate, were analyzed. Pathologic changes in the placenta were observed by hematoxylin-eosin staining. One-way analysis of variance, t-test, and χ(2) test were used for statistical analysis.

RESULTSMAP significantly increased for ApoC3+NS groups compared with WT+NS groups (P < 0.05), without significant difference in urine protein. Following L-NAME injection, MAP and urinary protein significantly increased for ApoC3+L-NA and WT+L-NA compared with the corresponding NS groups (P < 0.05), and the increase for ApoC3+L-NA was more obvious. Urinary protein levels in early ApoC3+L-NA and WT+L-NA significantly increased compared with the corresponding late groups (P < 0.05). Fetal absorption rate significantly increased and fetal and placental weights significantly decreased in early ApoC3+L-NA and WT+L-NA compared with the corresponding NS groups (P < 0.05), without significant difference in late ApoC3+L-NA and WT+L-NA groups. Fetal weight in early ApoC3+L-NA was significantly lower than in early WT+L-NA group (P < 0.05). Morphologic examination of placentas from early ApoC3+L-NA and WT+L-NA groups showed varying degrees of fibrinoid necrosis.

CONCLUSIONSApoC3 transgenic mice with abnormal lipid metabolism showed gestational hypertension. Adverse factors and early effect time could aggravate the PE-like symptoms for ApoC3 transgenic mice.

Animals ; Apolipoprotein C-III ; genetics ; metabolism ; Female ; Lipid Metabolism ; drug effects ; genetics ; Male ; Mice ; Mice, Transgenic ; NG-Nitroarginine Methyl Ester ; pharmacology ; Pre-Eclampsia ; genetics ; metabolism ; Pregnancy

Endocannabinoid anandamide (AEA) has protective effect on the heart against ischemia/reperfusion injury and arrhythmia, but the electrophysiological mechanism is unclear yet. In this study, the sinoatrial node (SAN) samples from New Zealand rabbits were prepared, and intracellular recording technique was used to elucidate the effect of AEA on the action potential (AP) of SAN pacemaker cells of rabbits and the mechanism. Different concentrations of AEA (1, 10, 100, 200, 500 nmol/L) were applied cumulatively. For some SAN samples, cannabinoid type 1 (CB1) receptor antagonist AM251, cannabinoid type 2 (CB2) receptor antagonist AM630, potassium channel blocker tetraethylammonium (TEA) and nitric oxide (NO) synthase inhibitor L-nitro-arginine methylester (L-NAME) were used before AEA treatment, respectively. We found that: (1) AEA (100, 200 and 500 nmol/L) not only shortened AP duration (APD), but also decreased AP amplitude (APA) (P < 0.05). (2) AM251, but not AM630, abolished the effect of AEA on APD shortening. (3) TEA and L-NAME had no influence on the AEA effect. These findings suggest that anandamide can decrease APA and shorten APD in SAN pacemaker cells of rabbits, which may be mediated by activation of CB1 receptors, and is related to blockade of calcium channels but not potassium channels and NO.
Action Potentials ; Animals ; Arachidonic Acids ; pharmacology ; Cannabinoid Receptor Antagonists ; pharmacology ; Endocannabinoids ; pharmacology ; Indoles ; pharmacology ; Myocytes, Cardiac ; drug effects ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide ; metabolism ; Piperidines ; pharmacology ; Polyunsaturated Alkamides ; pharmacology ; Potassium Channel Blockers ; pharmacology ; Pyrazoles ; pharmacology ; Rabbits ; Sinoatrial Node ; cytology

BACKGROUNDPreeclampsia, especially early onset of preeclampsia (PE), is a common and serious disorder with high maternal and perinatal morbidity and mortality. Dietary factor is one of the most important factors which may affect the occurrence and development of the disease. The aim of this study is to investigate the effects of dietary factors on pathological changes of liver and placenta in preeclampsia-like mouse model by establishing the model at multiple stages of gestation.

METHODSWild-type (WT) mice were injected subcutaneously with nitric oxide synthase (NOS) inhibitor L-arginine methyl ester (L-NAME, 50 mg×kg(-1)×d(-1)) to establish PE-like model (L-NAME group) at early-, mid-, and late-pregnant periods respectively; simultaneously, the control mice were injected with normal saline (NS group). All the groups were divided into subgroups, standard chow group (SC), and high-fat diet group (HF). ApoE(-/-) pregnant mice served as a control group. Systolic blood pressure (SBP), urine protein, and histopathologic changes of placenta and liver in all groups were observed and statistically analyzed.

RESULTSIn WT and apoE(-/-) L-NAME subgroups, blood pressure and urine protein were significantly higher than those in all the gestational age matched NS groups (P < 0.05). Compared to other groups, remarkable liver fatty infiltration and lipid storage in placenta were found in early- and mid-L-NAME subgroups in apoE(-/-) mice (P < 0.05), especially in the early- and mid-HF+L-NAME subgroups in apoE(-/-) mice (P < 0.05). More lipid storage droplets both in liver and placenta were found in ApoE(-/-) mice than that of WT groups (P < 0.05). Morphology histopathologic examination of placentas showed varying degrees of fibrinoid necrosis and villous interstitial edema in early- and mid-L-NAME both in HF and SC of apoE(-/-) and WT subgroups compared to NS controls (P < 0.05). But there was no significant difference between HF and SC subgroups (P > 0.05), and no difference between apoE(-/-) and WT groups (P > 0.05).

CONCLUSIONSPreeclampsia-like conditions could be induced by L-NAME in mice at different gestational stages. Both WT and apoE(-/-) genotype mice with preeclampsia-like symptoms in early and mid stages of pregnancy presented lipid deposition in the placenta and hepatic fatty infiltration. To alter the environmental condition by feeding high-fat diet was harmful to the mother and the fetus. High-fat diet aggravated the impact of liver fatty infiltration at early and mid gestational stages especially in the apoE(-/-) mouse model. These results further revealed the association between early-onset preeclampsia and the dysoxidation of fatty acids.

Animals ; Apolipoproteins E ; deficiency ; genetics ; Diet, High-Fat ; Female ; Genotype ; Liver ; drug effects ; metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Mutant Strains ; NG-Nitroarginine Methyl Ester ; pharmacology ; Placenta ; drug effects ; metabolism ; Pregnancy

Cinnamyl alcohol (CAL) is known as an antipyretic, and a recent study showed its vasodilatory activity without explaining the mechanism. Here we demonstrate the vasodilatory effect and the mechanism of action of CAL in rat thoracic aorta. The change of tension in aortic strips treated with CAL was measured in an organ bath system. In addition, vascular strips or human umbilical vein endothelial cells (HUVECs) were used for biochemical experiments such as Western blot and nitrite and cyclic guanosine monophosphate (cGMP) measurements. CAL attenuated the vasoconstriction of phenylephrine (PE, 1 microM)-precontracted aortic strips in an endothelium-dependent manner. CAL-induced vasorelaxation was inhibited by pretreatment with NG-nitro-L-arginine methyl ester (L-NAME; 10(-4) M), methylene blue (MB; 10(-5) M) and 1 H-[1,2,4]-oxadiazolole-[4,3-a] quinoxalin-10one, (ODQ; 10(-6) or 10(-7) M) in the endothelium-intact aortic strips. Atrial natriuretic peptide (ANP; 10(-8) or 10(-9) M) did not affect the vasodilatory effect of CAL. The phosphorylation of endothelial nitric oxide synthase (eNOS) and generation of nitric oxide (NO) were stimulated by CAL treatment in HUVECs and inhibited by treatment with L-NAME. In addition, cGMP and PKG1 activation in aortic strips treated with CAL were also significantly inhibited by L-NAME. Furthermore, CAL relaxed Rho-kinase activator calpeptin-precontracted aortic strips, and the vasodilatory effect of CAL was inhibited by the ATP-sensitive K+ channel inhibitor glibenclamide (Gli; 10(-5) M) and the voltage-dependent K+ channel inhibitor 4-aminopyridine (4-AP; 2 x 10(-4) M). These results suggest that CAL induces vasorelaxation by activating K+ channels via the NO-cGMP-PKG pathway and the inhibition of Rho-kinase.
Animals ; Aorta/drug effects/metabolism/physiology ; Atrial Natriuretic Factor/pharmacology ; Cyclic GMP/*metabolism ; Cyclic GMP-Dependent Protein Kinases/*metabolism ; Dipeptides/pharmacology ; Human Umbilical Vein Endothelial Cells/drug effects/metabolism ; Humans ; Male ; Methylene Blue/pharmacology ; NG-Nitroarginine Methyl Ester/pharmacology ; Nitric Oxide/*metabolism ; Nitric Oxide Synthase/metabolism ; Oxadiazoles/pharmacology ; Phenylephrine/pharmacology ; Phosphorylation ; Potassium Channel Blockers/pharmacology ; Potassium Channels/*agonists ; Propanols/*pharmacology ; Quinoxalines/pharmacology ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Vasoconstriction/*drug effects ; Vasodilation/drug effects ; rho-Associated Kinases/antagonists & inhibitors/*metabolism

PURPOSE: The purpose of this study was to examine effects of nitric oxide synthase (NOS) inhibitor on muscle weight and myofibrillar protein content of affected and unaffected hindlimb muscles in rats with neuropathic pain induced by unilateral peripheral nerve injury. METHODS: Neuropathic pain was induced by ligation and cutting of the left L5 spinal nerve. Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The NOSI group (n=19) had NOS inhibitor (L-NAME) injections daily for 14 days, and the Vehicle group (n=20) had vehicle injections daily for 14 days. Withdrawal threshold, body weight, food intake and activity were measured every day. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected from hindlimbs. Muscle weight and myofibrillar protein content of the dissected muscles were determined. RESULTS: The NOSI group showed significant increases as compared to the Vehicle group for body weight at 15 days, muscle weight and myofibrillar protein content of the unaffected soleus and gastrocnemius. The NOSI group demonstrated a higher pain threshold than the vehicle group. CONCLUSION: NOSI for 14 days attenuates unaffected soleus and gastrocnemius muscle atrophy in neuropathic pain model.
Animals ; Body Weight/drug effects ; Disease Models, Animal ; Eating/drug effects ; Enzyme Inhibitors/*administration & dosage/pharmacology ; *Hindlimb ; Male ; Muscle Fibers, Skeletal/*drug effects/metabolism ; Muscle Proteins/metabolism ; Muscular Atrophy/drug therapy ; NG-Nitroarginine Methyl Ester/*administration & dosage/pharmacology ; Neuralgia/*etiology ; Nitric Oxide Synthase/*antagonists & inhibitors/metabolism ; *Peripheral Nerve Injuries ; Rats ; Rats, Sprague-Dawley

BACKGROUNDThe lung is one of the most important organs that are sensitive to ischemia. We hypothesized that remote postconditioning (RPostC) induced by brief occlusion and reperfusion of the pulmonary artery could attenuate myocardial reperfusion injury.

METHODSThirty rabbits were randomized into three groups. Group ischemia-reperfusion (IR) (n = 10) were anesthetized rabbits subjected to 30-minute occlusion of the left anterior descending coronary artery followed by 180-minute reperfusion. Group RPostC (n = 10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion, and the left anterior descending coronary artery (LAD) occluded for 30 minutes with a 180-minute reperfusion. Group L-N(w)-nitro-L-arginine methylester (L-NAME) + RPostC (n = 10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion and intravenous infusion of L-NAME (10 mg/kg), and the LAD occluded for 30 minutes with a 180-minute reperfusion. Blood samples were taken for levels of creatine kinase (CK), superoxide dismutase (SOD) and malondialdehyde (MDA) at three different time points. At the end of the experiment, tissue samples of the infarcted region were harvested to calculate the cardiomyocyte apoptosis index (AI) by TUNEL. A piece of left and right lung tissue was harvested to evaluate the damage to the lung.

RESULTSAfter reperfusion for 180 minutes, the concentration of CK was lower in group RPostC, (4.79 ± 0.27) U/ml, than that in group IR, (6.23 ± 0.55) U/ml (P < 0.01), and group L-NAME + RPsotC, (5.86 ± 0.42) U/ml (P < 0.01). The concentration of MDA was lower in group RPostC, (6.06 ± 0.36) nmol/ml, than that in group IR, (11.41 ± 0.91) nmol/ml (P < 0.01), and group L-NAME + RPostC, (11.06 ± 0.62) nmol/ml (P < 0.01). The activity of SOD was higher in group RPostC, (242.34 ± 25.02) U/ml, than that in group IR, (148.05 ± 18.24) U/ml (P < 0.01), and group L-NAME + RPostC, (160.66 ± 9.55) U/ml (P < 0.01). The apoptosis index was lower in group RPostC, (14.25 ± 5.20)%, than that in group IR, (35.77 ± 10.09)% (P < 0.01), and group L-NAME + RPostC, (30.37 ± 7.76)% (P < 0.01). No significant difference caused by pulmonary ischemia was found in the lung tissue among the three groups.

CONCLUSIONSRPostC may attenuate myocardial ischemia-reperfusion injury connected to the activity of endothelial nitric oxide synthase. Brief pulmonary ischemia may not be harmful to lungs.

Animals ; Apoptosis ; drug effects ; Creatine Kinase ; blood ; Ischemic Preconditioning ; methods ; Lung ; metabolism ; Male ; Malondialdehyde ; blood ; Myocardial Reperfusion Injury ; metabolism ; Myocytes, Cardiac ; cytology ; drug effects ; metabolism ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide Synthase Type III ; antagonists & inhibitors ; metabolism ; Rabbits ; Superoxide Dismutase ; blood

BACKGROUNDPreeclampsia is one of hypertensive disorders in pregnancy. It is associated with abnormal lipid metabolism, including fatty acid oxidation metabolism. Long chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) plays an indispensable role in the oxidation of fatty acids. It has been reported that nitric oxide (NO) is one of the regulatory factors of the fatty acid oxidation pathway. The aim of this research was to investigate whether the nitric oxide synthase (NOS) inhibitor L-NAME may cause down-regulation of LCHAD in the pathogenesis of preeclampsia.

METHODSPregnant wild-type (WT) mice were treated with L-NAME or normal saline (NS) during gestation days 7 - 18 (early group), days 11 - 18 (mid group) and days 16 - 18 (late group), and apoE-/- mice served as a control. Systolic blood pressure (SBP), urine protein, feto-placental outcome, plasma lipid levels and NO concentrations were measured, and the expression of mRNA and protein for LCHAD in placental tissue were determined by real-time polymerase chain reaction (RT-PCR) and Western blotting, respectively.

RESULTSIn WT and apoE-/- mice, SBP and urinary protein increased following L-NAME injection. Fetal and placental weights and NO concentrations were reduced and total cholesterol, triglycerides and free fatty acid levels were increased in early and mid L-NAME groups in WT and apoE-/- mice, compared with the NS group. There was no significant difference between the late L-NAME group and NS group. RT-PCR and Western blotting analysis showed that the mRNA and protein levels of LCHAD expression were significantly down-regulated in the early and mid L-NAME groups but not in the late L-NAME group in the WT and apoE-/- mice compared with the corresponding NS groups.

CONCLUSIONSInhibition of NO in early and mid gestation in mice may cause hyperlipidemia and suppression of fatty acid oxidation, whereas preeclampsia-like conditions in late gestation may be a maternal vascular response to inhibition of NO.

Animals ; Disease Models, Animal ; Enzyme Inhibitors ; pharmacology ; Fatty Acids ; metabolism ; Female ; Mice ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide Synthase ; antagonists & inhibitors ; Oxidation-Reduction ; Pre-Eclampsia ; chemically induced ; etiology ; Pregnancy