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This work aimed to test both energy production and the recovering of phosphorus from high solid content digestate by coupling microbial electrochemical technologies (MET) with a crystallization process. Digestate coming from an anaerobic digester was used as the feeding substrate for a Microbial Fuel Cell (MFC) and a Microbial Electrolysis cell (MEC) to produce electricity and H2, promoting P removal (as struvite: MgNH4PO4∙6H2O) as consequence of the pH increase at the cathode level. MECs were equipped with low cost stainless steel mesh cathodes to be compared with a benchmark cathode, i.e. Pt electrode, and used to reduce the METs cost. The effluents coming from METs were then treated to further reduce P content by promoting struvite precipitation in a crystallization device, by adding either pure Mg salt (MgCl2) or an Mg by-product (seawater bitterns). MFC tests showed a Coulombic efficiency of 35%, with a volumetric power produced of 14.2 ± 0.15 W m−3. MEC (+1.07 V vs SHE) systems produced 1.90 ± 0.04 LH2 L−1d −1 using a stainless steel mesh (SSM) and 2.02 ± 0.03 LH2 L−1d −1 using a platinum cathode. Both MET treatments led to a phosphate (PO43−) reduction of between 21% and 30% and an organic load reduction (chemical oxygen demand) of between 27% and 44% of the digestate. The addition of MgCl2∗6H2O or seawater bitterns, in the molar ratio of 1.6: 1 (Mg:P) led to a further reduction of phosphate (PO43−) of between 60% and 70% with an overall reduction of phosphate (PO43−) of ≈90%. These results show how the MET systems could be used for COD and nutrients reduction as well as H2 or electricity production from digestate. Moreover, the SSM cathode gave a similar performance to the Pt cathode, while seawater bitterns seem to be useful in substituting MgCl2∗6H2O. The results obtained showed that the combination of the system proposed in this work with a biogas plant could be a low cost solution for the recovery of nutrients and for hydrogen or electricity generation from digestate.

Coronary blood flow and diastolic function are well known to interfere with each other through mechanical and metabolic mechanisms. We aimed to assess the relationship between coronary flow reserve (CFR) and diastolic dysfunction in patients suffering from angina but with normal coronary angiography. In 16 patients with chest pain and angiographically normal coronary arteries, CFR was measured using transthoracic echo-Doppler by inducing hyperemia through dipyridamole infusion. Diastolic function (E/A, deceleration time, isovolumetric relaxation time [IVRT], propagation velocity [Vp]) and left ventricular mass were evaluated by means of two-dimensional transthoracic echocardiography. The patients were initially divided into two groups on the grounds of CFR only (ACFR: altered CFR, n = 9; NACFR: unaltered CFR, n = 7). Thereafter they were divided into four groups on the grounds of CFR and diastolic function (NN: normal; AA: altered CFR/diastole; AN: altered CFR/normal diastole; NA: normal CFR/altered diastole). Most of the subjects were scheduled in AA (n = 8) or NA (n = 5) groups, which were taken into consideration for further analysis. Patients were not different regarding various risk factors. ACFR and AA patients were older with normal body weight in comparison with NACFR and NA patients (P

Various hindbrain nuclei have been demonstrated to be involved in the control of the cardiovascular reflexes elicited by both non-noxious and noxious gastric distension, through parasympathetic and sympathetic activation. The different role played by the branches of autonomic nervous system in exerting these effects and their crosstalk in relation to low-/high-pressure distension rate has not been examined yet. Therefore, in the present work, monolateral and bilateral vagotomy and splanchnicotomy were performed in anesthetised rats to analyse the involvement of hindbrain nuclei in haemodynamic changes caused by gastric distension at high (80 mmHg) and low (15 mmHg) pressure. The analysis of c-Fos expression in neuronal areas involved in cardiovascular control allowed us to examine their recruitment in response to various patterns of gastric distension and the crosstalk between vagal and splanchnic systems. The results obtained show that the low-pressure (non-noxious) gastric distension increases both heart rate and arterial blood pressure. In addition, the vagus nerve and hindbrain nuclei, such as nucleus ambiguous, ventrolateral medulla and lateral reticular nucleus, appear to be primarily involved in observed responses. In particular, we have found that although vagus nerve plays a central role in exerting those cardiovascular reflex changes at low gastric distension, for its functional expression an intact splanchnic system is mandatory. Hence, the absence of splanchnic input attenuates pressor responses or turns them into depressor responses. Instead at high-pressure (noxious) gastric distension, the splanchnic nerve represents the primary component in regulating the reflex cardiovascular effects.

This experimental study aimed to evaluate the ex-vivo three-dimensional (3-D) motion of the Inverted Arch Ring (IAR), an innovative new design concept for a flexible incomplete annuloplasty prosthesis with an incorporated stabilizing rigid arch that can be used in correcting mitral valve regurgitation. Twenty explanted porcine hearts were placed in a circulation simulation system. Ultrasonometry transducers implanted in the mitral annulus were used to measure the 3-D valvular motion during a simulated cardiac cycle. Annular distance measurements were recorded and compared in each heart before and after the implantation of the IAR prosthesis at pressures corresponding to mid-systole and mid-diastole. Distances measured in mid-systole and mid-diastole demonstrated no significant differences in annular motion or in valve areas either prior to or after IAR implantation. Therefore, the results of this study confirm the minimal effects exerted by the IAR prosthesis on the mitral valve&rsquo, s 3-D motion during a simulated cardiac cycle.

Des-acyl ghrelin (DAG), the most abundant form of ghrelin in humans, has been found to reduce arterial blood pressure and prevent cardiac and endothelial cell apoptosis. Despite this, data regarding its direct effect on cardiac function and coronary blood flow, as well as the related involvement of autonomic nervous system and nitric oxide (NO), are scarce. We therefore examined these issues using both in vivo and in vitro studies. In 20 anesthetized pigs, intracoronary 100 pmol/mL DAG infusion with a constant heart rate and aortic blood pressure, increased coronary blood flow and NO release, whereas reducing coronary vascular resistances (P < .05). Dose responses to DAG were evaluated in five pigs. No effects on cardiac contractility/relaxation or myocardial oxygen consumption were observed. Moreover, whereas the blockade of muscarinic cholinoceptors (n = 5) or α- and β-adrenoceptors (n = 5 each) did not abolish the observed responses, NO synthase inhibition (n = 5) prevented the effects of DAG on coronary blood flow and NO release. In coronary artery endothelial cells, DAG dose dependently increased NO release through cAMP signaling and ERK1/2, Akt, and p38 MAPK involvement as well as the phosphorylation of endothelial NO synthase. In conclusion, in anesthetized pigs, DAG primarily increased cardiac perfusion through the involvement of NO release. Moreover, the phosphorylation of ERK1/2 and Akt appears to play roles in eliciting the observed NO production in coronary artery endothelial cells.

Objective: To examine the effects of asenapine on nitric oxide (NO) release and Ca2+ transients in H9C2 cell line, which were either subjected to peroxidation or not. Materials and Methods: H9C2 were treated with asenapine alone or in presence of intracellular kinase blockers, serotoninergic and dopaminergic antagonists, and voltage Ca2+ channels inhibitors. Experiments were also performed in H9C2 treated with hydrogen peroxide. NO release and intracellular Ca2+ were measured through specific probes. Results: In H9C2, asenapine differently modulated NO release and Ca2+ movements depending on peroxidative condition. The Ca2+ pool mobilized by asenapine mainly originated from the extracellular space and was slightly affected by thapsigargin. Moreover, the effects of asenapine were reduced or prevented by kinases blockers, dopaminergic and serotoninergic receptors inhibitors, and voltage Ca2+ channels blockers. Conclusions: On the basis of our findings, we can conclude that asenapine by interacting with its specific receptors, exerts dual effects on NO release and Ca2+ homeostasis in H9C2; this would be of particular clinical relevance when considering their role in cardiac function modulation.

Artemetin is one of the main components of Achillea millefolium L. and Artemisia absinthium, which have long been used for the treatment of various diseases. To date, however, available information about protective effects of their extracts on the cardiovascular system is scarce. Therefore, we planned to analyze the effects of artemetin on nitric oxide (NO) release and the protection exerted against oxidation in porcine aortic endothelial (PAE) cells. In PAE, we examined the modulation of NO release caused by artemetin and the involvement of muscarinic receptors, β2-adrenoreceptors, estrogenic receptors (ER), protein-kinase A, phospholipase-C, endothelial-NO-synthase (eNOS), Akt, extracellular-signal-regulated kinases 1/2 (ERK1/2) and p38 mitogen activated protein kinase (p38 MAPK). Moreover, in cells treated with hydrogen peroxide, the effects of artemetin were examined on cell survival, glutathione (GSH) levels, apoptosis, mitochondrial membrane potential and transition pore opening. Artemetin increased eNOS-dependent NO production by the involvement of muscarinic receptors, β2-adrenoreceptors, ER and all the aforementioned kinases. Furthermore, artemetin improved cell viability in PAE that were subjected to peroxidation by counteracting GSH depletion and apoptosis and through the modulation of mitochondrial function. In conclusion, artemetin protected endothelial function by acting as antioxidant and antiapoptotic agent and through the activation of ERK1/2 and Akt. Copyright © 2015 John Wiley & Sons, Ltd.

Recently, vitamin D (VitD) has been recognized as increasingly importance in many cellular functions of several tissues and organs other than bone. In particular, VitD showed important beneficial effects in the cardiovascular system. Although the relationship among VitD, endothelium, and cardiovascular disease is well established, little is known about the antioxidant effect of VitD.Our objective was to study the intracellular pathways activated by VitD in cultured human umbilical vein endothelial cells undergoing oxidative stress.Nitric oxide production, cell viability, reactive oxygen species, the mitochondrial permeability transition pore, membrane potential, and caspase-3 activity were measured during oxidative stress induced by administration of 200 μM hydrogen peroxide for 20 minutes. Experiments were repeated in the presence of specific vitamin D receptor ligand ZK191784.Pretreatment with VitD alone or in combination with ZK191784 is able to reduce the apoptosis-related gene expression, involving both intrinsic and extrinsic pathways. At the same time, it has been shown the activation of pro-autophagic beclin 1 and the phosphorylation of ERK1/2 and Akt, indicating a modulation between apoptosis and autophagy. Moreover, VitD alone or in combination with ZK191784 is able to prevent the loss of mitochondrial potential and the consequent cytochrome C release and caspase activation.The present study shows that VitD may prevent endothelial cell death through modulation of the interplay between apoptosis and autophagy. This effect is obtained by inhibiting superoxide anion generation, maintaining mitochondria function and cell viability, activating survival kinases, and inducing NO production.

As in other organs, oxidative stress–induced injury and cell death may result from free oxygen radical–dependent mechanisms and alterations in signal transduction pathways leading to apoptosis. Among the new suggested therapies for injuries caused by oxidative stress, the use of levosimendan has been reported to be quite promising. In the present study, we aimed to examine the protective effects of levosimendan against liver oxidative stress in anesthetized rats and to analyze the involvement of mitochondrial adenosine triphosphate–dependent potassium (mitoKATP) channels and nitric oxide (NO). In 50 anesthetized rats, liver ischemia/reperfusion (I/R) was performed via nontraumatic portal occlusion. In some animals, levosimendan was infused into the portal vein at the onset of reperfusion, whereas other rats received the vehicle only. Moreover, in some rats, levosimendan was given after the intraportal administration of l-Nω-nitro-arginine methyl ester (l-NAME) or 5-hydroxydecanoate (5HD). The portal vein blood flow was measured, and blood samples were taken for the determination of transaminases, thiobarbituric acid reactive substances (TBARS), and reduced glutathione (GSH); liver biopsy samples were used for B cell lymphoma 2–associated X protein, caspase-9, Akt, and endothelial nitric oxide synthase (eNOS) activation through western blotting. Also, caspase-3 activity was measured. In rats, I/R caused an increase in apoptotic markers, transaminases, and TBARS and a decrease in GSH and Akt activation. Levosimendan administration was able to counteract oxidative damage and apoptosis in a dose-dependent way and to increase GSH, Akt, and eNOS activation. All effects of levosimendan were abolished by pretreatment with l-NAME and 5HD. In conclusion, the results of the present study show that levosimendan can exert protection against ischemic liver damage through mechanisms related to NO production and mitoKATP channel function. These data provide interesting perspectives into the use of levosimendan in hepatic surgery and transplantation. Liver Transpl 20:361-375, 2014. © 2013 AASLD.

Secretin has been implicated in cardiovascular regulation through its specific receptors, as well as through β-adrenoceptors and nitric oxide, although data on its direct effect on coronary blood flow and cardiac function have remained scarce. The present study aimed to determine the primary in vivo effect of secretin on cardiac function and perfusion and the mechanisms related to the autonomic nervous system, secretin receptors and NO. In addition, in coronary endothelial cells the intracellular pathways involved in the effects of secretin on NO release were also examined. In 30 pigs, intracoronary secretin infusion at 2.97 pg for each millilitre per minute of coronary blood flow at constant heart rate and aortic blood pressure increased coronary blood flow, maximal rate of change of left ventricular pressure, segmental shortening, cardiac output and coronary NO release (P

Background/Aims: The 1α,25-dihydroxycholecalciferol (Vit. D) induces eNOS dependent nitric oxide (NO) production in human umbilical vein endothelial cells (HUVEC). To our knowledge, there are no reports directly relating Vit. D induced NO production to proliferation and/or migration in endothelial cells (EC). The aim of this study was to evaluate whether Vit. D addition to porcine EC could affect their proliferation and/or migration in a three-dimensional matrix via NO production. Materials and Methods: Porcine aortic endothelial cells (PAE) were used to evaluate Vit. D effects on cell proliferation and migration in a three-dimensional matrix. Results: Vit. D induced NO production in PAE cells. Moreover, it induced a significant increase in cellular proliferation and migration in a three-dimensional matrix. These effects were NO dependent, as inhibiting eNOS activity by L-NAME PAE migration was abrogated. This effect was strictly related to MMP-2 expression and apparently dependent on Vit. D and NO production. Conclusions: Vit. D can promote both endothelial cells proliferation and migration in a three-dimensional matrix via NO-dependent mechanisms. These findings cast new light on the role of Vit. D in the angiogenic process, suggesting new applications for Vit. D in such fields as tissue repair and wound healing.

La chanson napolitaine est reconnue comme l'un des plus importants répertoires de chansons dans le monde ainsi que comme l'un des tous premiers exemples de musique populaire. Cependant, dans les années 1960 alors que les jeunes musiciens napolitains essayaient d'absorber et de développer les tendances contre-culturelles se développant sur l'ensemble du territoire italien à l'époque, un tel répertoire semblait se dresser en ennemi sur leur chemin. Cet article montre comment la musique napolitaine des cinquante dernières années a du s'écarter ou remodeler la chanson napolitaine classique afin de combattre son hégémonie et trouver son propre chemin, dans un pays changeant à vitesse grand V. Ce n'est qu'après un travail de « déconstruction » que la chanson napolitaine fut reprise et acceptée, enorgueillissant une nouvelle génération de chercheurs et de musiciens enthousiastes. Neapolitan Song is recognized as one of the most important repertoires of songs in the world and one of the first examples of popular music. Yet, in the 1960s, when the young Neapolitan musicians tried to absorb and develop the countercultural trends of the time which were spreading in Italy, such a repertoire seemed like an enemy on their way. This essay tells how the Neapolitan music of the last fifty years had to discard or reshape the classic Neapolitan Song in order to fight its hegemony and find its way to modernity in a country that was changing at fast speed. It is only after this work of ‘deconstruction’ that Neapolitan Song was recovered and re-accepted, boasting now a new generation of enthusiastic scholars and performers.

Neapolitan Song is recognized as one of the most important repertoires of songs in the world and one of the first examples of popular music. Yet, in the “60s, when the young Neapolitan musicians tried to absorb and develop the countercultural trends of the time which were spreading in Italy, such a repertoire seemed like an enemy on their way. This essay tells how the Neapolitan music of the last fifty years had to discard or reshape the classic Neapolitan Song in order to fight its hegemony and find its way to modernity in a country that was changing at fast speed. It is only after this work of “deconstruction” that Neapolitan Song was recovered and re-accepted, boasting now a new generation of enthusiastic scholars and performers. La chanson napolitaine est reconnue comme l'un des plus importants répertoires de chansons dans le monde ainsi que comme l'un des tous premiers exemples de musique populaire. Cependant, dans les années 1960 alors que les jeunes musiciens napolitains essayaient d'absorber et de développer les tendances contre-culturelles se développant sur l'ensemble du territoire italien à l'époque, un tel répertoire semblait se dresser en ennemi sur leur chemin. Cet article montre comment la musique napolitaine des cinquante dernières années a du s'écarter ou remodeler la chanson napolitaine classique afin de combattre son hégémonie et trouver son propre chemin, dans un pays changeant à vitesse grand V. Ce n'est qu'après un travail de « déconstruction » que la chanson napolitaine fut reprise et acceptée, enorgueillissant une nouvelle génération de chercheurs et de musiciens enthousiastes.

Ischemia/reperfusion (I/R) injury is an important cause of acute renal failure because of oxidative, inflammatory, and apoptotic mechanisms. The aim of the present study was to examine any possible protective effects of levosimendan in an in vivo pig model of renal I/R injury. In 40 anesthetized pigs (eight groups of five pigs each), I/R was induced by clamping-reopening the left renal artery. During ischemia, in three groups of pigs, levosimendan and the multiorgan preservation solution Custodiol, alone or in combination with levosimendan, were infused in the renal artery. In two other groups of animals, levosimendan in combination with Custodiol was administered after the intrarenal nitric-oxide (NO) synthase blocker N(ω)-nitro-L-arginine methyl ester (L-NAME) or the mitochondrial ATP-sensitive K(+) channel (K(ATP) channel) inhibitor 5-hydroxydecanoate (5-HD). In the other animals, saline, L-NAME, or 5-HD were administered alone. Throughout the experiments, urinary N-acetyl-β-glucosaminidase (NAG) release was measured, and renal function was assessed. Moreover, renal biopsy samples were taken for the detection of apoptosis and tissue peroxidation. In pigs treated with levosimendan or the combination of levosimendan and Custodiol, NAG, peroxidation, and apoptotic markers were lower than in animals treated with Custodiol alone. In addition, renal function was better preserved, and cell survival and antioxidant systems were more activated. All beneficial effects were prevented by L-NAME and 5-HD. In conclusion, levosimendan alone or in combination with Custodiol exerted better protection against renal I/R injuries than Custodiol alone through antioxidant, antiapoptotic, and prosurvival actions depending on mitochondrial K(ATP) channels and NO-related mechanisms.

In anesthetized pigs gastrin-17 increased coronary blood flow through CCK1/CCK2 receptors and β(2)-adrenoceptors-related nitric oxide (NO) release. Since the intracellular pathway has not been investigated the purpose of this study was to examine in coronary endothelial cells the CCK1/CCK2 receptors-related signaling involved in the effects of gastrin-17 on NO release. Gastrin-17 caused a concentration-dependent increase of NO production (17.3-62.6%; p

Acute cardiac failure caused by myocardial infarction or inadequate cardioprotection during heart surgery is associated with increased mortality and morbidity. Levosimendan is a new drug used in heart failure though it is limited by the systemic hypotension, which develops with intravenous administration. Intracoronary (IC) administration however should affect systemic circulation less while maintaining the beneficial cardiac effects of the drug. We herewith report the results from the first such clinical series. Levosimendan was administered IC in 33 consecutive patients who developed cardiogenic shock during heart surgery and were unable to wean off cardiopulmonary bypass despite maximal support. Preadministration/postadministration coronary graft flows, hemodynamic parameters, left ventricular function, and metabolic requirements were measured and compared. Levosimendan significantly increased graft flows and improved hemodynamic parameters. Systolic blood pressure (93 ± 26.4 vs. 106 ± 18.2 mm Hg, P < 0.05) and cardiac index (2.0 ± 0.5 vs. 3.1 ± 0.2, P < 0.001) were increased, whereas systemic vascular resistance (1470.7 ± 114 vs. 1195.8 ± 112, P < 0.01) was reduced. Better myocardial perfusion improved metabolic requirements, with myocardial oxygen extraction and glucose uptake increasing by 72% and 74%, respectively, whereas lactate production was reduced by 64%. Echocardiography demonstrated additional ventricular segment recruitment. Therefore, IC Levosimendan administration in acute heart failure is safe and efficacious producing improved cardiac function without significant detrimental hypotension.

Objective:Levosimendanhasbeenreportedtoexertcardioprotection.In thisstudy, wehaveexaminedthecardiaceffectsofdifferentdosesof intracoronary levosimendan on ischemia/reperfusion injuries, and the involvement of KATP channels and nitric oxide (NO). Methods: The experiments were performed in a total of 56 anesthetized pigs. In 21 pigs, 1.5, 5 and 12 mg min � 1 levosimendan was infused over 15 min into the coronary artery at the onset of 1 h reperfusion following 2-h ischemia and the effects on cardiac function, infarcted area, and on apoptosis/ autophagy were examined. In addition, the activation of Akt and extracellular receptor kinase (ERK) was analyzed. The findings were compared withthoseobtainedinafurther14pigswherethehighestdoselevosimendanwasinfusedafterglibenclamideand L-nitro-argininemethylester(LNAME). Results: Intracoronary 1.5, 5 and 12 mg min � 1 levosimendan caused an increase of segmental shortening, dP/dtmax and cardiac output of 7.8%, 22.6%, and 31.6%; 7.6%, 16.9%, and 21.6%; 2.8%, 5.9%, and 6.2%, respectively, from values measured at the end of ischemia. The beneficial effects elicited by levosimendan were still evident at the end of reperfusion when the increase of segmental shortening, dP/dtmax and cardiac output caused by the three doses of levosimendan amounted to 3.7%, 13.3%, and 16.5%; 1.5%, 9.4%, and 11%; 1.4%, 2.7%, and 3.9%, respectively. When doses of 5 and 12 mg min � 1 levosimendan were used, a reduction of infarcted area to about 69% and 67% of area at risk was observed, and was significantly different from that of about 79% measured in control animals. In addition, after intracoronary levosimendan, the inhibition of apoptosis and activation of autophagy and a dose-related increase of the level of phosphorylation of ERK and Akt were observed. These responses were completely prevented by glibenclamide and significantly reduced by L-NAME. Conclusions:The results of this study show that intracoronary levosimendan reduces cell death induced by ischemia/reperfusion in a dose-dependent manner and activates survival signaling through KATP channel opening and NO. These findings support interesting implications for cardioprotection in interventional cardiology and cardiac surgery. # 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Levosimendan exerts cardioprotection through mitochondrial K(ATP) (mitoK(ATP)) channels opening. In addition, intracoronary levosimendan was found to modulate programmed forms of cell death by nitric oxide (NO) involvement. The aim of this study was to examine the role of mitoK(ATP) channels and NO in the effects of levosimendan on apoptosis/autophagy. In H9c2 cells treated with hydrogen peroxide apoptosis/autophagy, survival signaling, cell viability, mitochondrial membrane potential, and permeability transition pore opening were analyzed through Western blot and colorimetric and fluorescence assays. Pretreatment of H9c2 cells with levosimendan was able to counteract the oxidative injuries caused by hydrogen peroxide. The effects of levosimendan were potentiated by diazoxide and were similar to those elicited by the autophagic activator rapamycin. The autophagic inhibitor 3-methyladenine reduced the effects of levosimendan, whereas after the pan-caspases inhibitor N-Acetyl-Asp-Glu-Val-Asp-al (Z-VAD.FMK), cell survival and autophagy in response to levosimendan increased. Both the mitoK(ATP) channels inhibition and the NO synthase blocking attenuated the cardioprotection elicited by levosimendan. The results have shown that levosimendan protects H9c2 cells against oxidative injuries through the modulation of the interplay between autophagy and apoptosis and the activation of survival signaling. The mitoK(ATP) channels and NO may be involved in such cardioprotection through interference with mitochondrial functioning.

The release of gastrointestinal hormones has been reported to modulate reflex cardiovascular responses caused by gastric distension, although the role played by gastrin 17 is as yet unknown. The present study was therefore planned to determine the primary in vivo effect of gastrin 17 on coronary blood flow and cardiac function and the involvement of autonomic nervous system, CCK1/2 receptors, and nitric oxide (NO). In 40 anesthetized pigs, gastrin 17 was infused into the left anterior descending coronary artery at constant heart rate and arterial blood pressure. In 35 of the 40 pigs, the mechanisms of the observed hemodynamic responses were analyzed by repeating gastrin 17 infusion after autonomic nervous system and NO blockade, and after specific CCK receptors agonists/antagonists administration. Intracoronary gastrin 17 administration caused dose-related increases of both coronary blood flow and cardiac function. The intracoronary co-administration of CCK33/pentagastrin and gastrin 17 potentiated the coronary effects observed when the above agents were given alone ( P

Background: Recently, 1α,25-dihydroxycholecalciferol (vitD) has received increasing interest for its effects on many tissues and organs other than bone. A number of experimental studies have shown that vitD may have an important role in modifying risk for cardiovascular disease. Aims: This study was planned to test the effects of vitD on endothelial nitric oxide (NO) production and to study the intracellular pathways leading to NO release. Methods: In human umbilical vein endothelial cells (HUVEC) cultures the effects of vitD on NO production and p38, Akt, ERK and eNOS phosphorylations were examined in absence or in presence of the NO synthase inhibitor L-NAME and protein kinases specific inhibitors SB203580, wortmannin and UO126. Results: VitD caused a concentration-dependent increase in NO production. The maximum effect was observed at a concentration of 1 nM and the optimal time of stimulation was 1 min. Effects induced by vitD were abolished by L-NAME and by pre-treatment with protein kinases inhibitors. To verify the effective involvement of vitD receptor (VDR) in the action mechanism of vitD, experiments were repeated in presence of the specific VDR ligands ZK159222 and ZK191784. Conclusions: The results of this study demonstrate that vitD can induce a significant increase in endothelial NO production. VitD interaction with VDR caused the phosphorylation of p38, AKT and ERK leading to eNOS activation.

Background: In endothelial cells urocortin II has recently been found to activate nitric oxide synthase through cAMP-dependent and Ca2+-related pathway. Aim: The present study was therefore planned to determine the mechanisms of urocortin II effect on Ca2+ movements. Methods. In Fura-2 loaded porcine aortic endothelial cells (PAE), the effects of urocortin II on [Ca2+]c were analyzed and compared with those of various K+ channels agonists/antagonists. Results: In Fura-2 loaded PAE, urocortin II promoted a transient increase of [Ca2+]c mainly originating from an intracellular pool sensitive to thapsigargin and slightly from the extracellular space. In addition, urocortin II caused the hyperpolarization of plasma membrane through the opening of K+ channels, which contributed to the increased [Ca2+]c. These effects were abolished by the corticotropin releasing factor receptors (CRFR2) blocker, the adenylyl cyclase and Ca2+-calmodulin-kinase (CaMKII) inhibitors and by blockers of K+ channels. In addition, in PAE cultured in Na+-free medium or loaded with the plasma-membrane Ca2+ pump inhibitor the urocortin II-evoked Ca2+ transient was slower. Conclusion: The results obtained show that urocortin II affects intracellular Ca2+ homeostasis in PAE by both promoting a discharge of intracellular pool and by interfering with the operation of store-dependent channels through CRFR2-cAMP-CaMKII related signalling and K+ channels opening.

Systemic intermedin (IMD)1–47 administration has been reported to result in vasodilation and marked hypotension through calcitonin-related receptor complexes. However, its effects on the coronary circulation and the heart have not been examined in vivo. The present study was therefore planned to determine the primary in vivo effect of IMD1–47 on coronary blood flow and cardiac function and the involvement of the autonomic nervous system and nitric oxide (NO). In 35 anesthetized pigs, IMD1–47, infused into the left anterior descending coronary artery at doses of 87.2 pmol/min, at constant heart rate and arterial blood pressure, augmented coronary blood flow and cardiac function. These responses were graded in a further five pigs by increasing the infused dose of IMD1–47 between 0.81 and 204.1 pmol/min. In the 35 pigs, the blockade of cholinergic receptors (intravenous atropine, 5 pigs), α-adrenoceptors (intravenous phentolamine, 5 pigs), and β1-adrenoceptors (intravenous atenolol, 5 pigs) did not abolish the cardiac response to IMD1–47, the effects of which were prevented by blockade of β2-adrenoceptors (intravenous butoxamine, 5 pigs), NO synthase (intracoronary Nω-nitro-l-arginine methyl ester, 5 pigs), and calcitonin-related receptors (intracoronary CGRP8–37/AM22–52, 10 pigs). In porcine coronary endothelial cells, IMD1–47 induced the phosphorylation of endothelial NO synthase and NO production through cAMP signaling leading to ERK, Akt, and p38 activation, which was prevented by the inhibition of β2-adrenoceptors, calcitonin-related receptor complexes, and K+ channels. In conclusion, IMD1–47 primarily augmented coronary blood flow and cardiac function through the involvement of calcitonin-related receptor complexes and β2-adrenoreceptor-mediated NO release. The intracellular signaling involved cAMP-dependent activation of kinases and the opening of K+ channels.

Background: Urocortin II has previously been shown in anesthetized pigs to increase coronary blood flow through activation of the endothelial nitric oxide synthase (eNOS) pathway and involvement of the subtype 2 of corticotropin releasing factor receptors (CRFR2). However, little information has been available regarding the intracellular signalling through these receptors and leading to the release of nitric oxide (NO). Aim: The present study was therefore planned to determine the mechanism involved in such signalling. Methods: In porcine aortic endothelial cells (PAE) the effects of urocortin II on NO production and ERK, Akt, p38 and eNOS phosphorylation were examined in absence or presence of the adenylyl cyclase agonist forskolin and antagonist 2’5’ dideoxyadenosine, the Ca2+ ionophore A23187, the Ca2+-calmodulin-kinase inhibitor KN93, the CRFR2 blocker astressin 2B and of the protein kinases specific inhibitors UO126, wortmannin and SB203580. Results: Urocortin II caused a significant increase of NO production, which was amplified by forskolin and A23187 (P 2+-related phoshorylation of ERK, Akt and p38 leading to eNOS activation.

Background and purpose: Levosimendan acts as a vasodilator through the opening of ATP-sensitive K+ channels (KATP) channels. Moreover, the coronary vasodilatation caused by levosimendan in anaesthetized pigs has recently been found to be abolished by the nitric oxide synthase (NOS) inhibitor Nω-nitro-L-arginine methyl ester, indicating that nitric oxide (NO) has a role in the vascular effects of levosimendan. However, the intracellular pathway leading to NO production caused by levosimendan has not yet been investigated. Thus, the purpose of the present study was to examine the effects of levosimendan on NO production and to evaluate the intracellular signalling pathway involved. Experimental approach: In porcine coronary endothelial cells (CEC), the release of NO in response to levosimendan was examined in the presence and absence of Nω-nitro-L-arginine methyl ester, an adenylyl cyclase inhibitor, KATP channel agonists and antagonists, and inhibitors of intracellular protein kinases. In addition, the role of Akt, ERK, p38 and eNOS was investigated through Western blot analysis. Key results: Levosimendan caused a concentration-dependent and K+-related increase of NO production. This effect was amplified by the mitochondrial KATP channel agonist, but not by the selective plasma membrane KATP channel agonist. The response of CEC to levosimendan was prevented by the KATP channel blockers, the adenylyl cyclase inhibitor and the Akt, ERK, p38 inhibitors. Western blot analysis showed that phosphorylation of the above kinases lead to eNOS activation. Conclusions and implications: In CEC levosimendan induced eNOS-dependent NO production through Akt, ERK and p38. This intracellular pathway is associated with the opening of mitochondrial KATP channels and involves cAMP.

We planned to determine the primary effects and mechanisms of urocortin II, a member of the corticotrophin-releasing factor (CRF) family highly expressed in the cardiovascular system, on coronary blood flow and myocardial function in vivo. Urocortin II was infused into the left anterior descending coronary artery in 25 anaesthetized pigs whilst measuring haemodynamic variables, coronary blood flow, ventricular dP/dt(max) cardiac output and percentage of segmental shortening. This infusion was repeated after blockade of the autonomic nervous system, nitric-oxide synthase (NOS) or subtype 2 of the CRF receptors. In all experiments changes in heart rate and aortic blood pressure were prevented. Intra-coronary urocortin II increased, within 60 s, coronary blood flow (15+/-3.2%, P

Background: Oral treatment with prednisone has demonstrated efficacy in reducing restenosis after percutaneous coronary interventions (PCI). However, administration of steroids at high dose may raise concerns in terms of applicability and tolerability. Monitoring the occurrence of possible side-effects is therefore mandatory. Methods: Secondary effects of oral prednisone in this setting is analyzed. The “expected” secondary effects of the steroid treatment are described, together with the “unexpected” occurrence of likely drug-induced neutropenia observed in patients prescribed prednisone and thienopyridines simultaneously after PCI. Results: Two-hundred and twenty patients were monitored for the occurrence of side-effects of the prednisone therapy. Twenty-eight patients (14%) had side-effects likely related to the prednisone treatment: gastric pain (4%), increment of arterial pressure needing upgrading of antihypertensive treatment (4%), edema (1.8%), and concomitant infections (1.4%). In three patients (1.4%), agranulocytosis was detected at the time of the routine blood cell count scheduled 4 weeks after PCI in otherwise asymptomatic patients. Neutropenia subsided completely after withdrawal of prednisone and thienopyridine in all cases and the blood cell formula normalized within 3 weeks. Conclusions: Side-effects of oral prednisone given after PCI to reduce restenosis occur in less than 15% of patients. Complaints are mild and reversible and can be easily managed with adjunctive diuretic and antacid drugs. The occurrence of agranulocytosis after prednisone had never been reported before, but was observed in 1.4% of our patients receiving simultaneously a thienopyridine. To explain such an unusual event we propose the hypothesis of a possible metabolic interaction between prednisone and thienopyridines.

Background: Previous work found that extracts from the roots of Salvia miltiorrhiza, a Chinese medicinal herb, reduced alcohol intake in selectively bred Sardinian alcohol-preferring (sP) rats. The present study was designed to evaluate whether miltirone, one of the possible active constituents of S. miltiorrhiza, might be responsible for the reducing effect of the extracts on alcohol intake. Methods: An initial experiment assessed the effect of 100 mg/kg (intragastric, i.g.) of 4 extracts of S. miltiorrhiza, differing in miltirone content (0, 2, 3, and 7%, respectively), on alcohol intake in alcohol-experienced sP rats exposed to the 2-bottle “alcohol (10%, volume in volume) versus water” choice regimen. Subsequently, the effect of pure miltirone (2.5–10 mg/kg, i.g., i.e., a dose range comparable to its content in the effective doses of the active extracts) on acquisition and maintenance of alcohol-drinking behavior was evaluated in alcohol-naive and alcohol-experienced sP rats exposed to the 2-bottle choice regimen. The effect of miltirone (10 mg/kg, i.g.) on blood alcohol levels was assessed after the i.g. and intraperitoneal (i.p.) administration of alcohol. Finally, the effect of miltirone (30–100 mg/kg, i.g.) on the severity of alcohol withdrawal syndrome was evaluated in Wistar rats made physically dependent on alcohol by the repeated administration of intoxicating doses of alcohol. Results: The reducing effect of 4 different extracts of S. miltiorrhiza on alcohol intake was positively and significantly correlated with their miltirone content. Pure miltirone reduced alcohol intake in alcohol-experienced rats and delayed acquisition of alcohol-drinking behavior in alcohol-naive rats. Similar to S. miltiorrhiza extracts, miltirone markedly reduced blood alcohol levels when alcohol was administered i.g. but not i.p., suggesting that miltirone hampered alcohol absorption from the gastrointestinal system. Finally, miltirone failed to affect the severity of alcohol withdrawal syndrome in alcohol-dependent rats. Conclusions: The results of the present study suggest that miltirone is the likely active constituent of S. miltiorrhiza responsible for the reducing effect of its extracts on alcohol intake in different experimental models of excessive alcohol consumption.

Regional intra-arterial infusion of human placental lactogen in anaesthetized pigs has been shown to cause coronary, renal and iliac vasoconstriction by antagonizing the vasodilatory effects of beta2-adrenergic receptors. Since nitric oxide is known to modulate or mediate beta2-adrenergic effects, the present study was planned in the same experimental model to determine the role of nitric oxide in the above vascular responses to human placental lactogen. In eight pigs anaesthetized with sodium pentobarbitone, changes in anterior descending coronary, left renal and left internal iliac blood flow caused by intra-arterial infusion of human placental lactogen at constant heart rate and arterial blood pressure were assessed using electromagnetic flowmeters. Intra-arterial infusion of the human placental lactogen caused decreases in coronary, renal and iliac blood flow which, respectively, averaged 16.7, 8.1 and 12.2% of the baseline values. The role of nitric oxide in this response was studied in the same pigs by repeating the experiments, after measured blood flows had returned to baseline values, following intra-arterial administration of N(omega)-nitro-L-arginine methyl ester (L-NAME). The subsequent intra-arterial infusion of human placental lactogen did not cause any significant changes in measured blood flows, even when performed after reversing the increase in arterial blood pressure and coronary, renal and iliac resistance caused by L-NAME with continuous intravenous infusion of papaverine. These results indicate that the coronary, renal and iliac vasoconstriction caused by human placental lactogen, known to involve antagonism of beta2-adrenergic vasodilatory effects, was mediated by inhibition of nitric oxide release.

Recent studies have demonstrated that treatment with the gamma-aminobutyric acid (GABA(B)) receptor agonist, baclofen, reduces alcohol intake in selectively bred Sardinian alcohol-preferring rats tested under the homecage two-bottle "alcohol versus water" choice regimen. This study was designed to investigate whether baclofen also reduces alcohol-reinforcing effects in Sardinian alcohol-preferring rats. To this aim, sP rats were trained to lever press for oral alcohol (15%, vol/vol) or sucrose (0.3%, wt/vol; included as alternative reinforcer to evaluate the specificity of baclofen effect on alcohol reinforcement) under a fixed ratio schedule of 4. Once steady levels of alcohol or sucrose self-administration behavior were established, the effects of acutely administered baclofen (0, 1.7, and 3 mg/kg, intraperitoneal [ip]) and naloxone (0, 1, and 3 mg/kg, ip; included as reference compound) on alcohol- or sucrose-reinforced responding were evaluated. Baclofen administration dose dependently, although not specifically, reduced alcohol-reinforced responding to an extent comparable to that of naloxone. Baclofen also produced a dose-dependent and specific delay in the onset of alcohol-reinforced responding, suggesting that it suppressed the rats' motivation to start drinking alcohol. These data are discussed in terms of adding further support to the hypothesized involvement of the GABA(B) receptor in the neural system mediating alcohol reinforcement. These data are also in agreement with the results of recent preliminary clinical studies suggesting that baclofen may have therapeutic efficacy in the treatment of alcohol dependence.

Recent surveys suggest that positive outcomes in the pharmacotherapy of alcoholism may be obtained through drug combinations. The present study evaluated the effect of the combination of the opioid receptor antagonist, naltrexone, with the GABA B receptor agonist, baclofen, on the acquisition of alcohol drinking behavior in Sardinian alcohol-preferring (sP) rats. Rats were treated with either saline, 0.5 mg/kg naltrexone, 1 mg/kg baclofen, or 0.5 mg/kg naltrexone plus 1 mg/kg baclofen once a day for 10 days. Alcohol was offered immediately after the first drug injection under the 2-bottle regimen. Alcohol intake in saline-treated rats rose to 5–6 g/kg/day within a few days, indicative of a rapid acquisition of alcohol drinking behavior. Neither naltrexone nor baclofen, when given alone, affected alcohol drinking behavior. In contrast, the drug combination resulted in a significant reduction in daily alcohol intake and retardation in the acquisition of alcohol drinking behavior. These results suggest that combination of naltrexone plus baclofen may result in a synergistic reduction in alcohol intake in sP rats. These results are discussed in terms of naltrexone and baclofen exerting a concomitant and reciprocally potentiating inhibitory action on alcohol-induced activation of mesolimbic dopamine transmission.

The renin-angiotensin system (RAS) is an ancient and complex cascade of homeostatic reactions aimed at regulating primordial functions that ensure organ perfusion through the control of blood pressure and the regulation of renal-cardiac activity. However, the over-expression or lack of compensatory mechanisms of any of its components may initiate detrimental effects that potentially lead to disease, a balance that makes the RAS a sequence with a labile physiological equilibrium and with a strong harm potential. These characteristics of the RAS in general, and of the angiotensin converting enzyme (ACE) in particular, make it not only an important complex for the regulation of blood pressure and neuropeptide metabolism, but also a fascinating subject of study from a biochemical, evolutionary and genetic point of view. Pharmacological interventions that influence the RAS by inhibiting the ACE or the angiotensin II type 1 receptor (AT1R) have demonstrated sustained efficacy in reducing the incidence of cardiovascular events and, consequently, vascular mortality in several clinical situations. ACE inhibitors and angiotensin II receptor antagonists (ARAs) reduce blood pressure and have cardio- and vasculoprotective effects. Anti-atherosclerotic effects have also been attributed to these drugs. For these reasons, it has been hypothesised that RAS inhibitors could also reduce the recurrence of ischaemic events after myocardial revascularisation procedures, namely coronary artery by-pass graft surgery (CABG) or percutaneous coronary interventions (PCI). Information available on the effect of ACE inhibitors and ARAs in patients with coronary artery disease (CAD) previously treated with revascularisation techniques indicates a substantial reduction of mortality and infarction in these patients. However, data regarding the progression of CAD, restenosis or reocclusion of vascular conduits of the coronary circulation after myocardial revascularisation are inconsistent. In most studies, the administration of ACE inhibitors neither improved the ischaemic threshold nor reduced the need for new revascularisation procedures. On the contrary, ACE inhibitors have been associated with higher restenosis rates after PCI in some retrospective series. Conversely, a single, exploratory randomised trial demonstrated that the selective AT1R antagonist valsartan significantly reduced stent restenosis after PCI. In patients undergoing CABG, ACE inhibitors did not reduce the risk of graft degeneration or occlusion. Studies that evaluated a possible anti-atherosclerotic effect of ACE inhibitors (including some large randomised trials) have generally been negative.

The occurrence of benzimidazole fungicides (benomyl and its metabolites carbendazim, thiabendazole and thiophanate-methyl) in 50 banana samples imported to Italy from Ecuador, Panama and Costa Rica during 2002–2003 was investigated. In 11 samples, thiabendazole was found at concentrations ranging from 0.050 to 2.510 mg/kg. In five samples, carbendazim was found at concentrations ranging from 0.140 to 1.100 mg/kg, whereas thiophanate-methyl was not detected in any sample. Analysis was carried out using HPLC-DAD and positive samples were confirmed by GC–MS. Recoveries of carbendazim, thiabendazole and thiophanate-methyl at four fortification levels (0.5, 1.0, 2.5 and 4.0 mg/kg) were in the range 81–96% for carbendazim and thiabendazole and 63.2–69.8% for thiophanate-methyl. Only two samples contained carbendazim that exceeded the FAO/WHO Codex Alimentarius and the Italian Department of Health maximum residue limits.

Infusion of insulin in anaesthetized pigs has been shown to cause an increase in renal blood flow and a decrease in coronary blood flow, which were the net result of a vasoconstriction involving sympathetic α-adrenoceptor-mediated mechanisms and of a local vasodilatation involving the endothelial release of nitric oxide. In the present study, the effect of insulin on superior mesenteric blood flow was examined in pentobarbitone-anaesthetized pigs at constant heart rate, aortic blood pressure, left ventricular contractility and blood levels of glucose and potassium. In 10 pigs, infusion of 0.004 IU kg −1 min−1 of insulin increased mesenteric flow. In five of these pigs, intravenous phentolamine enhanced the increase in mesenteric flow elicited by insulin, a response which was abolished by the subsequent injection of Nω-nitro-l-arginine methyl ester (l-NAME) into the mesenteric artery. In the remaining five pigs, infusion of insulin after intramesenteric injection of l-NAME caused a decrease in mesenteric flow. This response was abolished by the subsequent intravenous administration of phentolamine. The present study showed that infusion of insulin in anaesthetized pigs primarily caused a mesenteric vasodilatation, which was the net result of two opposite effects, namely a predominant vasodilatation mediated by the endothelial release of nitric oxide and a sympathetic vasoconstrictor mechanism mediated by α-adrenoceptors.

Extensive research suspecting an association between plasma levels of dehydroepiandrosterone and the risk of coronary heart disease has not been conclusive. The present study was designed to investigate the effect of dehydroepiandrosterone on the coronary circulation and to determine the mechanisms involved. In prepubertal pigs of both sexes anaesthetized with sodium pentobarbitone, changes in left circumflex or anterior descending coronary flow caused by intravenous infusion of dehydroepiandrosterone were assessed using an electromagnetic flowmeter. Changes in heart rate and arterial pressure were prevented by atrial pacing and by connecting the arterial system to a pressurized reservoir containing Ringer solution. In 20 pigs, infusion of 1 mg h−1 of dehydroepiandrosterone caused a decrease in coronary flow without affecting left ventricular dP/dtmax (rate of change of left ventricular systolic pressure) and filling pressures of the heart. In a further eight pigs, a dose–response curve was obtained by graded increases in the infused dose of hormone between 0.03 and 4 mg h−1. The mechanisms of the above response were studied in the 20 pigs by repeating the experiment after haemodynamic variables had returned to the control values observed before infusion. Blockade of muscarinic cholinoceptors with intravenous atropine (five pigs) and of α-adrenoceptors with intravenous phentolamine (five pigs) did not affect the dehydroepiandrosterone-induced coronary vasoconstriction. This response was abolished by blockade of β-adrenoceptors with intravenous propranolol (five pigs) and of coronary nitric oxide synthase with intracoronary injection of Nω-nitro-l-arginine methyl ester (five pigs) even after reversing the increase in arterial pressure and coronary vascular resistance caused by the two blocking agents with intravenous infusion of papaverine. The present study showed that intravenous infusion of dehydroepiandrosterone primarily caused coronary vasoconstriction. The mechanisms of this response were shown to involve the inhibition of a vasodilatory β-adrenergic receptor-mediated effect related to the release of nitric oxide.

The present paper describes the results of recent preclinical and clinical studies conducted in this laboratory in order to characterize the anti-alcohol properties of the GABA(B) receptor agonist, baclofen. At a preclinical level, the repeated administration of non-sedative doses of baclofen dose-dependently suppressed the acquisition and maintenance of alcohol drinking behavior in selectively bred Sardinian alcohol-preferring (sP) rats tested under the homecage, 2-bottle "alcohol vs water" choice regimen. Acute injection of baclofen completely blocked the temporary increase in voluntary alcohol intake occurring after a period of alcohol abstinence (the so-called alcohol deprivation effect, which models alcohol relapses in human alcoholics). Acute treatment with baclofen also dose-dependently suppressed extinction responding for alcohol (an index of motivation to consume alcohol) in sP rats trained to lever-press for oral alcohol self-administration. Taken together, these results suggest the involvement of the GABA(B) receptor in the neural substrate mediating alcohol intake and alcohol motivational properties in an animal model of excessive alcohol consumption. Further, acutely administered baclofen dose-dependently reduced the severity of alcohol withdrawal signs in Wistar rats made physically dependent upon alcohol. Preliminary clinical surveys suggest that the anti-alcohol properties of baclofen observed in rats may generalize to human alcoholics. Indeed, a double-blind survey demonstrated that repeated daily treatment with baclofen was associated, when compared to placebo, with a higher percentage of subjects totally abstinent from alcohol and a higher number of days of total abstinence. Treatment with baclofen also suppressed the number of daily drinks and decreased the obsessive and compulsive components of alcohol craving. Finally, a single non-sedative dose of baclofen resulted in the rapid disappearance of alcohol withdrawal symptomatology, including delirium tremens, in alcohol-dependent patients. In both clinical studies, baclofen was well tolerated with minimal side effects. These results suggest that baclofen may represent a potentially effective medication in the treatment of alcohol-dependent patients.

‘If you are an Italian living in Italy you do not need to make it obvious that you are Italian, and nothing pushes to reflect on what it is that makes you as such. But if you are an immigrant, you ...

Salvia miltiorrhiza extracts have been reported to suppress acquisition and maintenance of alcohol drinking behavior in Sardinian alcohol-preferring (sP) rats. The present study investigated whether IDN 5082, a standardized extract of Salvia miltiorrhiza, was capable of preventing, in sP rats, the development of the so-called alcohol deprivation effect (ADE), i.e. the transient increase in alcohol intake that occurs in laboratory animals after a period of alcohol deprivation. Interestingly, ADE has been proposed to model alcohol relapses in human alcoholics. The acute, intragastric administration of 25, 50, and 100 mg/kg IDN 5082 resulted in the complete suppression of the extra amount of alcohol consumed during the first hour of re-access to alcohol after 7 days of deprivation. These results suggest that IDN 5082 may possess anti-relapse properties.

Alcohol deprivation effect (ADE), i.e. the transient increase in alcohol intake that takes place in laboratory animals after a period of alcohol deprivation, has been proposed to model alcohol relapses in alcoholics. The present study investigated the effect of the GABA(B) receptor agonist, baclofen, on the development of ADE in selectively bred Sardinian alcohol-preferring (sP) rats. Acute administration of non-sedative doses of baclofen (0, 1, 1.7 and 3 mg/kg, i.p.) resulted in the complete suppression of the extra-amount of alcohol consumed during the first hour of re-access to alcohol after 7 days of deprivation. These results implicate the GABA(B) receptor in the neural substrate mediating ADE and suggest that baclofen may possess anti-relapse properties.

A previous study demonstrated that an extract of Salvia miltiorrhiza, a medicinal herb highly valued in Chinese folk medicine for the treatment of different pathologies, including insomnia, was capable of reducing voluntary alcohol intake in selectively bred Sardinian alcohol-preferring (sP) rats. The present study was designed to evaluate the suitability of different emulsifying, suspending agents and solvents as vehicles through which Salvia miltiorrhiza extracts can exert their reducing effect on alcohol intake. A single dose (100 mg/kg) of a standardised extract of Salvia miltiorrhiza was dissolved in either pure Polysorbate 80, arachis oil, PEG 400, or Polyoxyl 35 castor oil, or suspended in 0.5% CMC in water, and administered acutely by gavage to sP rats. A significant and specific reduction in alcohol intake was recorded only in rats treated with the combination of Polysorbate 80 plus the Salvia miltiorrhiza extract. A further experiment demonstrated that the ability of the combination of Polysorbate 80 in water plus the Salvia miltiorrhiza extract to decrease alcohol intake was dependent upon the concentration of Polysorbate 80. The results of the present study demonstrate that Polysorbate 80 is a proper vehicle for unravelling the reducing effect of Salvia miltiorrhiza extracts on alcohol intake. The ability of Polysorbate 80 to form micelles with the active ingredient(s) of the Salvia miltiorrhiza may explain these results. They may also offer relevant information for pharmaceutical preparation of Salvia miltiorrhiza extract to be used in future clinical trials.

Gastric distension in anaesthetized pigs reflexly elicits peripheral vasoconstriction and an increase in plasma renin activity (PRA), with vagal afferent and sympathetic efferent limbs. The aim of the present study was to quantify the contribution of the renin-angiotensin system to the peripheral vasoconstriction. In pigs anaesthetized with alpha-chloralose, changes in anterior descending coronary, superior mesenteric and left external iliac blood flow caused by stomach distension before and after blockade of angiotensin II receptors with losartan were assessed using electromagnetic flowmeters. Gastric distension for periods of 30 min was performed by injecting 0.8 l warm Ringer solution into balloons positioned within the viscus. Changes in heart rate and renal blood flow were prevented by atrial pacing and injection of phentolamine into the renal arteries, and changes in regional perfusion pressure and in baroreceptor activity were minimized by aortic constriction and denervation of the carotid sinuses. PRA was assessed by radioimmunoassay of angiotensin I. Before blockade of angiotensin II receptors by administration of losartan, stomach distension decreased coronary blood flow by 14.2 % in six pigs and mesenteric and iliac blood flow by 11 % and 17.3 %, respectively, in another six pigs. After administration of losartan, these decreases were significantly reduced to 7.4 %, 6.8 % and 8.7 %, respectively. The above responses were abolished by bilateral section of the subdiaphragmatic vagal nerves. These results show that the peripheral vasoconstriction reflexly caused by stomach distension was significantly contributed to by the concomitant activation of the renin-angiotensin system.

Recent studies demonstrated that treatment with the gamma-aminobutyric acid (GABA)(B) receptor agonist baclofen reduced alcohol intake in selectively bred Sardinian alcohol-preferring (sP) rats tested under the home-cage, two-bottle choice regimen.The present study investigated the effect of baclofen on the appetitive, rather than consummatory, aspects of alcohol ingestion in sP rats.Rats were trained to lever-press for oral alcohol (10%, v/v) or sucrose (3%, w/v) under a fixed-ratio schedule of 4. Once self-administration behavior was established, alcohol intake averaged approximately 0.7 g/kg over the 30-min session. Subsequently, the effect of the acute administration of baclofen (0, 1, 2 and 3 mg/kg, i.p.) on the extinction responding for alcohol and sucrose (defined as the maximal number of lever responses reached in the absence of reinforcement and used as index of motivation to consume alcohol and sucrose) was evaluated. RESULTS. All doses of baclofen produced a marked suppression of extinction responding for alcohol. Conversely, only the 3-mg/kg baclofen dose significantly affected extinction responding for sucrose. A separate open-field test indicated that baclofen (0, 1, 2 and 3 mg/kg, i.p.) did not affect spontaneous motor activity in sP rats.These results suggest that baclofen may specifically reduce the motivational properties of alcohol; further, these results are in agreement with the recently reported anti-craving potential of baclofen in alcoholics.