Hawthorn revisited: time- and dose-dependent cardioprotective action of WS-1442 special extract in the reperfusion-induced arrhythmia model in rats in vivo.

Standardized WS-1442 extract from Crataegus oxycantha (hawthorn) leaves and berries is one of the most widely studied preparations received from hawthorn. This popular substance is known from its positive influence on the cardiovascular system. The current research aimed to evaluate the optimal dose of standardized WS-1442 extract and the most beneficial period for its use. The study analysis was based on experiments previously conducted on male Sprague-Dawley rats (n = 152). The animals were divided into subgroups to examine the relationship between the dose-dependent (n = 96) and time-dependent (n = 56) effects of the mentioned extract. The research was performed based on the modified early reperfusion-induced arrhythmias model in vivo. The following parameters were assessed during the study: efficiency of mortality index reduction, reduction of ventricular arrhythmias incidences as well as the influence of standardized WS-1442 extract on hemodynamic parameters and amount of biochemical marker of cardiac tissue damage (creatine kinase). The current study revealed the dose- and time-dependent cardioprotective effect of standardized WS-1442 extract. It was expressed by mortality index reduction, decrease in the incidence and duration of severe ventricular arrhythmias and decline in the total amount of creatine kinase. Analyzed data coming from a model of reperfusion-induced arrhythmias in rats suggests that standardized WS-1442 extract is a potent cardioprotective agent whose action depends on both dose and intake time.

Crataegus special extract WS 1442: up-to-date review of experimental and clinical experiences.

Extracts and tinctures made from Crataegus spp. (Hawthorn) have been used as cardioprotective remedies since ancient times. WS 1442 special extract, manufactured by Dr. W. Schwabe Pharmaceuticals©, made from Crataegus spp. Leaves and flowers is one of the most studied and popular of preparations received from Hawthorn. It is integral, and most important active component of such herbal drugs as Crataegutt® novo 450, and CardioMax®. This standardized extract contains 18.75% oligomeric procyanidins (OPC), which have beneficial cardioprotective values and play a role as free-radicals scavengers, that protect the ischemic heart tissue from neutrophile elastase action successions. Moreover, WS 1442 also carries proven vasorelaxant activity, via affecting eNOS synthase, and prevents ischemic heart tissue swelling by influence on calcium signaling pathways, and thus detain hyperpermeability of endothelium. Actions of WS 1442 special extract were investigated in in vitro as well as in vivo studies including large clinical trials. In this review authors present current state of knowledge about possible beneficial effects of WS 1442 special extract on cardiovascular system.

Efficacy of short-term adjunctive subantimicrobial dose doxycycline in diabetic patients--randomized study.

OBJECTIVE: To investigate the effectiveness of short-term adjunctive subantimicrobial dose doxycycline (SDD) treatment in patients with diabetes mellitus type 2 and chronic periodontitis (CP). METHODS: Thirty-four patients with CP and type 2 diabetes mellitus were included in the placebo-controlled, double-blind study. After scaling and root planing (SRP), patients were randomly assigned to two groups, receiving either SDD or placebo bid for 3 months. The probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), approximal plaque index, glycated hemoglobin (HbA1c) level were recorded and gingival crevicular fluid (GCF) samples were collected at baseline and after 3-month therapy for the estimation of matrix metalloproteinase-8 levels. RESULTS: Clinical attachment level, PD, and BOP improved significantly in both groups after therapy (P < 0.05). The statistically significant difference between the two groups after the therapy was observed only in PD in tooth sites with initial PD ≥ 4 mm (SRP + placebo: 3.41 ± 0.6 mm vs SRP + SDD: 2.92 ± 0.5 mm, P < 0.05). GCF matrix metalloproteinase-8 levels were significantly reduced only in SRP + SDD group (P < 0.01). There were no changes in HbA1c levels after therapy. CONCLUSION: The short-term administration of SDD gives significant benefit at tooth sites with moderate disease (PD ≥ 4 mm) when compared to SRP alone in patients with diabetes and CP.

Comparison of ropivacaine and articaine with epinephrine for infiltration anaesthesia in dentistry - a randomized study.

AIM: To compare the efficacy, onset time and duration of maxillary infiltration anaesthesia with 0.5% plain ropivacaine or 4% articaine with epinephrine 1 : 100 000 and to determine their possible influence on cardiovascular parameters. METHODOLOGY: Sixty volunteers received 1.8 mL of the anaesthetic for buccal infiltration anaesthesia of maxillary central and lateral incisors and canine teeth without caries, restorations or signs of pulpitis. The efficacy, onset time and duration of pulp anaesthesia were assessed with an electric pulp tester. The duration of numbness of the upper lip was also monitored. Blood pressure and heart rate were measured before and after administration of the solutions. RESULTS: The efficacy of anaesthesia of lateral and central incisors was 100% for both anaesthetics. There were insignificant differences in effectiveness of canine pulp anaesthesia. The mean onset time was significantly (P < 0.05) shorter for ropivacaine (2.22 min) when compared with articaine (4.08 min). The duration of action and soft tissue anaesthesia were also significantly (P < 0.05) longer for ropivacaine (79.2 and 264 min) when compared with articaine (63.7 and 195.2 min, respectively). Ropivacaine caused significant (P < 0.05) increases in blood pressure and heart rate. CONCLUSIONS: Ropivacaine (0.5%) achieved effective and long duration of uninflamed pulp and soft tissue anaesthesia. Ropivacaine could be useful for long-lasting operative procedures without the need for a vasoconstrictor.

Differential action of two prolactin isoforms on ischemia and re-perfusion-induced arrhythmias in rats in vivo.

BACKGROUND: The different influences of one of the PRL isoforms (PRL I) on the cardiovascular system have been described in the past. AIM: Our goal was to establish an appropriate iv dose of 2 PRL isoforms (PRL I and PRL II) in intact rats. After establishing this dose, PRL I (0.01 mg/kg) or PRL II (0.001 mg/kg) was administered in bolus 10 min before left anterior descending coronary artery occlusion (7 min) followed by re-perfusion (15 min). We then aimed to study and compare the effects of these isoforms on ischemia- and re-perfusion-induced arrhythmias in the ischemia and re-perfusion-induced arrhythmias model in rats. MATERIALS AND METHODS: Mortality index, ventricular fibrillation and tachycardia (VF, VT) incidence and duration, systolic, diastolic, and mean arterial blood pressure, heart rate and myocardial index of oxygen consumption [pressure rate product (PRP)] were measured and calculated. RESULTS: Both PRL isoforms reduced animal mortality (from 50 to 18.75 and 25%, respectively). PRL II significantly reduced VF incidence (to 25%) as well as VT duration (18.21 ± 3.09) and these effects were markedly different from PRL I and from the control group (p<0.05). Both PRL reduced PRP in the recovery phase (p<0.05). CONCLUSIONS: We proved that supraphysiological doses of PRL isoforms administered in bolus could protect against sudden cardiac death as well as severe arrhythmias episodes during re-perfusion. Because of PRL's positive influence on the cardiovascular system and as an endogenous, well-tolerated substance, it might be of potential clinical use.

The time course of tumor necrosis factor-alpha, inducible nitric oxide synthase and vascular endothelial growth factor expression in an experimental model of chronic myocardial infarction in rats.

An injury to the heart due to myocardial infarction may progress to heart failure. Among the cytokines and growth factors whose interactions promote remodeling of the heart, increased expression of tumor necrosis factor (TNF)-alpha, inducible nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) has been found. However, little is known about the sequence of gene expression during the progression of heart injury. In the present study, male Sprague-Dawley rats were used for experimental myocardial infarction performed by ligation of the left anterior descending coronary artery. TNF-alpha, iNOS and VEGF expression was assessed by reverse transcription polymerase chain reaction. Localization of TNF-alpha, VEGF and iNOS protein was assessed by immunohistochemistry. An in vitro proliferation (BrdU incorporation) and differentiation (tube formation) assay of human umbilical vein endothelial cells was performed. The expression of TNF-alpha, iNOS, VEGF(164) and VEGF(188) was observed during the whole period after myocardial infarction (on days 1, 4, 11, 28 and 40), whereas VEGF(120) was found only on day 1 and 4. The most intense immunostaining for TNF-alpha was observed at the border zone. The iNOS immunostaining was initially located in the endothelium, whereas later it was also present in the walls of larger vessels. The VEGF protein was present in the border zone. No gene expression or immunostaining was detected in sham-operated rats. The in vitro experiments showed both proangiogenic (low TNF-alpha concentration, short period of incubation) and antiangiogenic (high TNF-alpha concentration, long period of incubation) effects of TNF-alpha. The expression of TNF-alpha and iNOS genes with the concomitant occurrence of a decrease in VEGF(120), VEGF(188) and VEGF(164) protein could be related to insufficient angiogenesis and may suggest the possible involvement of these events in remodeling after myocardial infarction.

Relation between expression of TNF alpha, iNOS, VEGF mRNA and development of heart failure after experimental myocardial infarction in rats.

An injury to the heart due to myocardial infarction (MI) may progress to heart failure. Among factors, whose interactions promote remodeling of ischemic myocardium, the increased expression of tumor necrosis factor alpha (TNFalpha), inducible nitric oxide synthase (iNOS) and Vascular Endothelial Growth Factor (VEGF) was found. However, little is known about the temporal and spatial relation between expression of iNOS, cytokine TNFalpha, and growth factor VEGF during pathological process of development of heart failure after the myocardial infarction. Male Sprague-Dawley rats were used for experimental myocardial infarction. The procedure was performed by anterolateral thoracotomy and snearing LAD with the metal clip. The hemodynamic measurements were done with the Langendorff preparation converted into a working heart system. The hemodynamic parameters were recorded at day 6, 11, 28, 40 and the myocardium for gene expression was collected at day 1, 4, 11, 28, 40. Control group was sham operated rats. The VEGF, TNFalpha, iNOS, and GAPDH genes were detected by RT-PCR assay from samples taken at border zone of myocardial infarction. Expression of isoform VEGF120 was found at day 1 and 4 after MI, whereas isoforms VEGF164 and VEGF188 along with expression of TNFalpha and iNOS was found at day 1, 4, 11, 28, 40. No expression of examined genes was detected in the myocardium of control rats. The expression of studied factors was parallel with development of heart failure after myocardial infarction assessed by hemodynamic measurements. These findings confirm the postulated involvement of TNFalpha, iNOS and growth factor VEGF in the remodeling of the myocardium and development of heart failure after experimental myocardial infarction.

[In vitro and in vivo studies on the cardioprotective action of oligomeric procyanidins in a Crataegus extract of leaves and blooms]. / In-vitro- und In-vivo-Untersuchungen zur kardioprotektiven Wirkung von oligomeren Procyanidinen in einem Crataegus-Extrakt aus Blättern mit Blüten.

Cardioprotective effects of a standardized extract from leaves with flowers of Crataegus (WS-1442; content of oligomeric procyandins [OPC]: 18.75%) have recently been demonstrated in an ischemia-reperfusion model in rats. Further studies were now conducted to clarify the mechanism of action and to identify active constituents involved in these effects of WS-1442. Exhausting partitioning between ethyl acetate/water and successive ultrafiltration of the aqueous layer led to the quantitative recovery of three fractions, which were tested for their in vitro radical scavenging (RS) and human neutrophil elastase (HNE) inhibitory activity. The lipophilic ethylacetate-soluble fraction A, enriched in flavone derivatives and constituting 14.9% of WS-1442, was as active as WS-1442 in inhibiting HNE. However, its RS activity was only about half that of the primary extract. Although 67.9% of WS-1442 was recovered in a water-soluble low molecular weight fraction B, this fraction displayed only weak RS and HNE inhibiting activity. In contrast, the RS and HNE inhibiting potencies of an essentially flavone-free and OPC-rich fraction C (21.3% of WS-1442) were significantly higher (inhibition of lipid peroxidation: IC50 0.3 microgram/ml; inhibition of HNE: IC50 0.84 microgram/ml) as those of WS-1442. The RS and HNE inhibitory activities of the extract and those of its fractions correlated well with their OPC-content but not with their concentration of flavonols. These results demonstrate that OPCs of Crataegus extracts possess stronger radical scavenging activities than flavone derivatives or other constituents. In addition, the oligomeric components are potent inhibitors of HNE. Oral administration of 20 mg/kg/d of the OPC-rich fraction C to rats afforded similar protection against ischemia-reperfusion induced pathologies as treatment with WS-1442 at a dose of 100 mg/kg/d. These observations indicate that radical scavenging and elastase inhibitory activities could indeed be involved in the observed cardioprotective effects of WS-1442, and demonstrate that OPCs are major orally active constituents of WS-1442. Thus, Crataegus extracts used therapeutically for cardiovascular diseases should be analyzed and standardized for their OPC-content.

A new concept of the isolated perfused heart preparation with on-line computerized data evaluation.

A modified perfusion apparatus for electrophysiological, hemodynamic and metabolic studies on hearts of small animal (e.g., rat, guinea pig) has been described. The apparatus consisted of two oxygenators connected to the aortic cannula of the Langendorff perfused heart, each one of which could be used on demand. The constant aortic perfusion pressure was controlled by oxygenating gas (5% CO2 in O2, usually). The perfusing medium could be changed easily and quickly without interruption. Left ventricular pressure was recorded by means of a balloon-catheter, while special suction electrodes obtained the high-amplitude, noise-free electrogram recordings. The coronary effluent partial pressure of oxygen (Po2) was continuously monitored, which enabled the calculation of myocardial oxygen consumption (MVO2). The effluent partial pressure of carbon dioxide (Pco2) and pH value were also measured simultaneously. A computerized system of data acquisition, calculation, storage, and end report has also been described. In this study, the influence of indomethacin on hypoxia-induced hemodynamic and metabolic changes in the isolated guinea pig heart was observed. The advantages and disadvantages of the described and standard Langendorff apparatus have been discussed also.

Central action of PGE1 on the cerebral neurotransmission; the cardiovascular response.

PGE1 administered in a single dose of 27 nmol intracerebroventricularly (icv) into the rats under urethane anaesthesia caused a long-lasting increase of the blood pressure and tachycardia. Phenoxybenzamine given 60 min before (20 mg/kg ip) blocked the hypertension and tachycardia evoked by PGE1 icv administration. Moreover, reserpine (10 mg/kg ip) given 24 h before PGE1 injection caused similar effects. Previous degeneration of the central adrenergic neurons (6-hydroxydopamine, 2 x 250 micrograms icv) also reduced both exerted effects by PGE1 icv. From the experiments carried out it results that central cardiovascular effects of PGE1 are due to the intact cerebral neurotransmission. These described effects could be common with direct PGE1 action upon adrenergic receptors from indirect effects due to release of noradrenaline by PGE1 in the central nervous system (CNS) in rats.

Influence of verapamil on central and peripheral effects of prostacyclin on circulatory system in rats.

The influence of verapamil on cardiovascular effects of prostacyclin (PGI2) in rats was examined. PGI2 administered into the lateral brain ventricle (i.c.v.) or intravenously (i.v.) in a dose of 2.7 x 10(-8)mol evoked hypotension and tachycardia. Pretreatment with verapamil in a dose of 2.0 x 10(-5)mol/kg given intraperitoneally (i.p.) diminished hypotensive effect of PGI2 i.c.v. as well as inhibiting the influence of PGI2 i.c.v. and i.v. upon the heart rate. Bolus injection of PGI2 in a dose of 2.7 x 10(-10), 2.7 x 10(-9) or 2.7 x 10(-8)mol evoked biphasic inotropic and chronotropic effects on isolated rat heart. Short-term increase of the contractile force together with bradycardia and afterwards long-lasting decrease of contractility with sustained, slight tachycardia were observed. Verapamil in a concentration of 1.0 x 10(-6)M blocked biphasic inotropic effect and bradycardia after PGI2 administration. Because some central and peripheral cardiovascular effects of PGI2 were inhibited by verapamil, it is concluded that PGI2 may participate in transmembrane calcium ions movements.

Central effects of leukotriene C4 and D4 in rats and mice.

Leukotrienes (LTs) C4 or D4 in a dose of 12 nmoles were administered into the lateral ventricle (i.c.v.) of the rat brain under urethane anaesthesia, and the changes in the blood pressure, heart and respiratory rate were investigated. In other animals the behaviour was evaluated by means of the open field test, and the rectal body temperature was measured. Besides, the content of noradrenaline, 5-hydroxytryptamine and 5-hydroxyindole acetic acid was estimated in different parts of the brain following i.c.v. application of LTs. In mice the antinociceptive effect of LTs in a dose of 1.5 nmoles was examined in the hot plate test; furthermore, the effect of LTs on chlorpromazine catalepsy was measured. Only LTC4 caused a slight rise of the peripheral blood pressure, a decreased respiratory rate and affected the behaviour of rats. Both LTs decreased the rectal body temperature but did not alter the content of biogenic amines in the brain of rats. In mice both LTs did not change the reactivity to thermic pain stimulus; only LTC4 intensified chlorpromazine catalepsy. The results indicate that both LTs exert slight biological effects upon the central nervous system; however, it should be emphasized that LTC4 has a stronger effect.

Influence of H2 receptors blockade upon some central effects of prostacyclin in rats.

Prostacyclin (PGI2) administered icv into the lateral rat brain ventricle in a dose of 1 and 10 micrograms caused hypothermia and catalepsy. Joint administration of PGI2 and chlorpromazine produced a greater cataleptic effect than that observed after the neuroleptic alone. Cimetidine (CMT) 2 g/kg po administered 60 min before PGI2 icv injection inhibited hypothermic and cataleptogenic action of PGI2. CMT blocked the cataleptogenic effect of chlorpromazine as well as combination of it with PGI2. CMT inhibited cataleptogenic effect of haloperidol, but it did not block the catalepsy induced by joint administration of haloperidol and PGI2. PGI2 did not change concentration of noradrenaline and dopamine in different brain areas. The results indicate that H2 receptors take part in some central pharmacological effects of PGI2 in rats.

Effect of H2 receptor blockade upon hypothermic, cataleptogenic and antinociceptive action of prostacyclin (PGI)2 administered into the lateral rat brain ventricle.

Prostacyclin (PGI2) administered i.c.v. into the lateral rat brain ventricle in a dose of 1 and 10 micrograms causes hypothermia, catalepsy as well as a mild analgesic effect. Joint administration of PGI2 along with chloropromazine or morphine produces a greater cataleptic effect than that observed after application of neuroleptics and morphine alone. Cimetidine (CMT) (2 g/kg p.o.) administered 60 min before intraventricular PGI2 injection inhibits hypothermic and cataleptogenic action of the investigated prostaglandin. CMT blocks cataleptogenic effect of chloropromazine and morphine as well as the combination of these two substances with PGI2. CMT inhibits the cataleptogenic effect of haloperidol, but it does not block the catalepsy induced by joint administration of haloperidol and PGI2. CMT does not modify the analgesic action of PGI2. The results indicate that H2 receptors take part in some central pharmacological effects of PGI2 in rats.

Antinociceptive and behavioral effects of leu-enkephalin (LENK) or D-Ala2-met-enkephalinamide (DAMEA) in rats after central chemical sympathectomy or serotoninectomy.

In rats with central chemical sympathectomy induced by two injections into the lateral brain ventricle (icv) of 250 micrograms of 6-hydroxydopamine or with central chemical serotoninectomy induced by 75 micrograms of 5,6-dihydroxytryptamine icv the antinociceptive and behavioral effects of LENK (200 micrograms icv) or DAMEA (10 or 20 micrograms icv) were examined. The chemical lesion of central noradrenaline or dopamine neurons or specific lesion of serotonin neurons abolished antinociceptive effects of LENK and DAMEA. Both peptides inhibited exploratory activity of rats. Central chemical serotoninectomy but not sympathectomy reversed some behavioral effects induced by LENK and DAMEA. These results suggest modulatory influence of the central noradrenaline and serotonin neurons in the antinociceptive mechanism of action of enkephalins and the participation of the central serotonin neurons on the behavior of rats induced by enkephalins.

Central effects of D-Ala2-met-enkephalinamide on the blood pressure of rats after central chemical sympathectomy or serotoninectomy.

D-Ala2-met-enkephalinamide (DAMEA) in ethyl urethane anesthetised rats increased the blood pressure, decreased heart rate and frequency of respirations. DAMEA could act centrally as well as peripherally after the penetration from the cerebro-spinal into the blood stream. These effects were blocked by naloxone. 6-Hydroxydopamine inhibited the circulatory and respiratory action of DAMEA. 5,6-Dihydroxytryptamine reversed this action of DAMEA. It is suggested that central presynaptic catecholamine and serotonin neurons modulate the central effects of DAMEA on the circulatory system and respiration in rats.

Role of H2 receptors in the central and peripheral effects of prostacyclin [PGI2] on circulatory system in rats.

PGI2 1 or 10 micrograms iv caused a decrease of blood pressure and bradycardia in rats. PGI2 administered into lateral ventricle of rat brain [icv] exerted hypotensive effect and tachycardia. PGI2 10 micrograms icv increased histamine level in the hypothalamus and cortex of rat's brain, but it did not influence histamine content in the blood. Cimetidine [CMT] given 60 min earlier per os inhibited bradycardia caused by PGI2 iv administration and diminished hypotensive action and tachycardia produced by PGI2 icv.