In vitro anti-Candida Activity of Zataria multiflora Boiss

Zataria multiflora Boiss known as Avishan Shirazi (in Iran)is one of the valuable Iranian medicinal plants. The aim ofstudy was to evaluate anti-Candida activity of Z. multifloraagainst different species of Candida in vitro. Anti-Candidaactivity of the aqueous, ethanolic and methanolic macerationextract of the aerial parts of Z. multiflora Boiss was studiedin vitro. Anti-Candida activity against Candida species wasdone using serial dilutions of extracts in Sabouraud's dextroseagar. Minimal inhibitory concentration (MIC) of the methanolicand ethanolic extracts was 70.7 and 127 mg l^–1, respectively.Aqueous extract showed no remarkable activity against Candidaspecies. We conclude that methanolic extract of the aerial partsof Z. multiflora Boiss has more anti-Candida effect at 70.7mg l^–1 compared to ethanolic extract 127 mg l^–1.In addition, the isolates of Candida parapsilosis were moresusceptible to methanolic extract than other tested species.     

Antiprotozoan and Antiviral Activities of Non-cytotoxic Truncated and Variant Analogues of Mussel Defensin

We previously reported the crucial role displayed by loop 3of defensin isolated from the Mediterranean mussel, Mytilusgalloprovincialis, in antibacterial and antifungal activities.We now investigated antiprotozoan and antiviral activities ofsome previously reported fragments B, D, E, P and Q. Two fragments(D and P) efficiently killed Trypanosoma brucei (ID₅₀ 4–12µM) and Leishmania major (ID₅₀ 12–45 µM) ina time/dose-dependent manner. Killing of T. brucei started asearly as 1 h after initiation of contact with fragment D andreached 55% mortality after 6 h. Killing was temperature dependentand a temperature of 4°C efficiently impaired the abilityto kill T. brucei. Fragments bound to the entire external epitheliumof T. brucei. Prevention of HIV-1 infestation was obtained onlywith fragments P and Q at 20 µM. Even if fragment P wasactive on both targets, the specificity of fragments D and Qsuggest that antiprotozoan and antiviral activities are mediatedby different mechanisms. Truncated sequences of mussel defensin,including amino acid replacement to maintain 3D structure andincreased positive net charge, also possess antiprotozoan andantiviral capabilities. New alternative and/or complementaryantibiotics can be derived from the vast reservoir of naturalantimicrobial peptides (AMPs) contained in marine invertebrates.     

Juice powder concentrate and systemic blood pressure, progression of coronary artery calcium and antioxidant status in hypertensive subjects: a pilot study

Because micronutrients from plants may have beneficial cardiovasculareffects, the hypothesis that an encapsulated juice powder concentratemight affect several measures of vascular health was testedin free living adults at low cardiovascular risk. Blood pressure,vascular compliance, lipid and antioxidant markers, and serialelectron beam tomography (to calculate a coronary artery calciumscore as a measure of atherosclerosis burden), were monitoredin 51 pre-hypertensive and hypertensive subjects over 2 years.By the end of follow-up, systolic and diastolic blood pressuredecreased significantly (–2.4 ± 1.0 mmHg, P <0.05 and –2.2 ± 0.6 mmHg, P < 0.001), and largeartery compliance improved significantly (1.9 ± 0.6 mlmmHg^–1 x 100, P < 0.01). The progression of coronaryartery calcium score was smaller than expected compared witha historical database (P < 0.001). Laboratory testing showeda significant decrease in homocysteine (P = 0.05), HDL cholesterol(P = 0.025) and Apo A (P = 0.004), as well as a significantincrease in β-carotene, folate, Co-Q10 and -tocopherol(all P < 0.001). The phytonutrient concentrate we utilizedinduced several favorable modifications of markers of vascularhealth in the subjects. This study supports the notion thatplant nutrients are important components of a heart healthydiet.     

Anti-anxiety Activity Studies on Homoeopathic Formulations of Turnera aphrodisiaca Ward

Turnera aphrodisiaca Ward (Turneraceae) has been traditionallyused for the treatment of anxiety neurosis, and as an aphrodisiac.Mother tinctures (85% ethanol extracts) of T. aphrodisiaca havealso been used for the treatment of central nervous system disorders.In the present investigation, T. aphrodisiaca mother tincturesformulated by three reputed manufacturers of homoeopathic medicines(NLK, DWSG and SBL) were evaluated for their anxiolytic activity.Dried mother tinctures of T. aphrodisiaca were subjected toanxiolytic activity evaluation at various doses, i.e. 50, 75,100, 125 or 150 mg/kg p.o. in mice using elevated plus mazeapparatus. Dried mother tinctures exhibited significant anxiolyticactivity at 50 mg/kg (NLK), 75 mg/kg (DWSG) and 125 mg/kg (SBL),respectively, with reference to control as well as standard(diazepam, 2 mg/kg p.o.). Mother tinctures of T. aphrodisiacaavailable in the market, have significant anxiolytic activity.Amongst the three mother tinctures of T. aphrodisiaca analyzed,the dry residue of NLK possesses the highest amount of anxiolyticconstituent(s). To ensure uniformity and consistency of biologicaleffects in herbal formulations, these should be standardizedon the basis of bioactive markers. The authors are activelyinvolved in isolating the bioactive constituent(s) from T. aphrodisiacaso that the plant can be standardized on the basis of biologicallyactive constituent(s).     

Inhibitory Response of Raphanus sativus on Lipid Peroxidation in Albino Rats

In the present study, inhibitory effect of the methanol extractof Raphanus sativus root on lipid peroxidation has been carriedout in normal rats. Graded doses of methanol extract of rootof the plant (40, 80 and 120 mg kg^–1 body weight) wereadministered orally for 15 days to experimental treated rats.Distilled water was administered to experimental control rats.At the end of experiment, rats were killed by decapitation afterether anesthesia. Blood and liver were collected to measurethiobarbituric acid reactive substance, reduced glutathioneand activity of catalase. Results indicated that the extractof R. sativus root reduced the levels of thiobarbituric acidreactive substance significantly in all experimental treatedgroups (P < 0.05) as compared to the experimental controlgroup. It also increased the levels of reduced glutathione andincreased the activity of catalase. In vitro experiments withthe liver of experimental control and experimental treated ratswere also carried out against cumene hydroperoxide induced lipidperoxidation. The extract inhibited in vitro cumene hydroperoxideinduced lipid peroxidation. R. sativus inhibits lipid peroxidationin vivo and in vitro. It provides protection by strengtheningthe antioxidants like glutathione and catalase. Inclusion ofthis plant in every day diet would be beneficial.     

Benefits of Zataria multiflora Boiss in Experimental Model of Mouse Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic condition of theintestine with unknown etiology involving multiple immune, geneticand environmental factors. We were interested to examine theeffect of total extract from Zataria multiflora Boiss, a folkmedicinal plant on prevention and treatment of experimentalIBD. Z. multiflora was administered (400, 600, 900 p.p.m.) throughdrinking water to IBD mice induced by intrarectal administrationof acetic acid. Prednisolone was used as the standard drug forcomparison. Biochemical, macroscopic and microscopic examinationsof colon were performed. Biochemical evaluation of inflamedcolon was done using assay of myeloperoxidase (MPO) activityand thiobarbituric acid reactive substances (TBARS) concentrationas indicators of free radical activity and cell lipid peroxidation.The activity of MPO and lipid peroxidation products (TBARS)increased in acetic acid-treated groups while recovered by pretreatmentof animals with Z. multiflora (400–900 p.p.m.) and prednisolone.Z. multiflora (600 and 900 p.p.m.) and prednisolone-treatedgroups showed significantly lower score values of macroscopicand microscopic characters when compared with the acetic acid-treatedgroup. The beneficial effect of Z. multiflora (900 p.p.m.) wascomparable with that of prednisolone. The antioxidant, antimicrobialand anti-inflammatory potentials of Z. multiflora might be themechanisms by which this herbal extract protects animals againstexperimentally induced IBD. Proper clinical investigation shouldbe carried out to confirm the activity in human.     

Roots of Withania somnifera Inhibit Forestomach and Skin Carcinogenesis in Mice

We evaluated the cancer chemopreventive efficacy of the Withaniasomnifera root, which has been used in the Indian traditionalmedicine system for many centuries for the treatment of variousailments. Since, studies showing its mechanism-based cancerchemopreventive efficacy are limited, this was investigatedin the present study. We studied the effect of dietary administrationof Withania root on hepatic phase I, phase II and antioxidantenzymes by estimation of its level/activity, as well as in attenuatingcarcinogen-induced forestomach and skin tumorigenesis in theSwiss albino mouse model. Our findings showed that roots ofW.somnifera inhibit phase I, and activates phase II and antioxidantenzymes in the liver. Further, in a long-term tumorigenesisstudy, Withania inhibited benzo(a)pyrene-induced forestomachpapillomagenesis, showing up to 60 and 92% inhibition in tumorincidence and multiplicity, respectively. Similarly, Withaniainhibited 7,12-dimethylbenzanthracene-induced skin papillomagenesis,showing up to 45 and 71% inhibition in tumor incidence and multiplicity.In both studies, Withania showed no apparent toxic effects inmice as monitored by the body weight gain profile. Together,these findings suggest that W.somnifera root has chemopreventiveefficacy against forestomach and skin carcinogenesis and warrantsthe identification and isolation of active compounds responsiblefor its anticancer effects, which may provide the lead for thedevelopment of antitumor agents.     

Ozone Therapy on Cerebral Blood Flow: A Preliminary Report

Ozone therapy is currently being used in the treatment of ischemicdisorders, but the underlying mechanisms that result in successfultreatment are not well known. This study assesses the effectof ozone therapy on the blood flow in the middle cerebral andcommon carotid arteries. Seven subjects were recruited for thetherapy that was performed by transfusing ozone-enriched autologousblood on 3 alternate days over 1 week. Blood flow quantificationin the common carotid artery (n = 14) was performed using colorDoppler. Systolic and diastolic velocities in the middle cerebralartery (n = 14) were estimated using transcranial Doppler. Ultrasoundassessments were conducted at the following three time points:1) basal (before ozone therapy), 2) after session #3 and 3)1 week after session #3. The common carotid blood flow had increasedby 75% in relation to the baseline after session #3 (P <0.001) and by 29% 1 week later (P = 0.039). In the middle cerebralartery, the systolic velocity had increased by 22% after session#3 (P = 0.001) and by 15% 1 week later (P = 0.035), whereasthe diastolic velocity had increased by 33% after session #3(P < 0.001) and by 18% 1 week later (P = 0.023). This preliminaryDoppler study supports the clinical experience of achievingimprovement by using ozone therapy in peripheral ischemic syndromes.Its potential use as a complementary treatment in cerebral lowperfusion syndromes merits further clinical evaluation.     

Antidiabetes and Anti-obesity Activity of Lagerstroemia speciosa

The leaves of Lagerstroemia speciosa (Lythraceae), a SoutheastAsian tree more commonly known as banaba, have been traditionallyconsumed in various forms by Philippinos for treatment of diabetesand kidney related diseases. In the 1990s, the popularity ofthis herbal medicine began to attract the attention of scientistsworldwide. Since then, researchers have conducted numerous invitro and in vivo studies that consistently confirmed the antidiabeticactivity of banaba. Scientists have identified different componentsof banaba to be responsible for its activity. Using tumor cellsas a cell model, corosolic acid was isolated from the methanolextract of banaba and shown to be an active compound. More recently,a different cell model and the focus on the water soluble fractionof the extract led to the discovery of other compounds. Theellagitannin Lagerstroemin was identified as an effective componentof the banaba extract responsible for the activity. In a differentapproach, using 3T3-L1 adipocytes as a cell model and a glucoseuptake assay as the functional screening method, Chen et al.showed that the banaba water extract exhibited an insulin-likeglucose transport inducing activity. Coupling HPLC fractionationwith a glucose uptake assay, gallotannins were identified inthe banaba extract as components responsible for the activity,not corosolic acid. Penta-O-galloyl-glucopyranose (PGG) wasidentified as the most potent gallotannin. A comparison of publisheddata with results obtained for PGG indicates that PGG has asignificantly higher glucose transport stimulatory activitythan Lagerstroemin. Chen et al. have also shown that PGG exhibitsanti-adipogenic properties in addition to stimulating the glucoseuptake in adipocytes. The combination of glucose uptake andanti-adipogenesis activity is not found in the current insulinmimetic drugs and may indicate a great therapeutic potentialof PGG.     

Neuroprotection by Brazilian Green Propolis against In vitro and In vivo Ischemic Neuronal Damage

We examined whether Brazilian green propolis, a widely usedfolk medicine, has a neuroprotective function in vitro and/orin vivo. In vitro, propolis significantly inhibited neurotoxicityinduced in neuronally differentiated PC12 cell cultures by either24 h hydrogen peroxide (H₂O₂) exposure or 48 h serum deprivation.Regarding the possible underlying mechanism, propolis protectedagainst oxidative stress (lipid peroxidation) in mouse forebrainhomogenates and scavenged free radicals [induced by diphenyl-p-picrylhydrazyl(DPPH). In mice in vivo, propolis [30 or 100 mg/kg; intraperitoneallyadministered four times (at 2 days, 1 day and 60 min before,and at 4 h after induction of focal cerebral ischemia by permanentmiddle cerebral artery occlusion)] reduced brain infarctionat 24 h after the occlusion. Thus, a propolis-induced inhibitionof oxidative stress may be partly responsible for its neuroprotectivefunction against in vitro cell death and in vivo focal cerebralischemia.     

Anti-stress and Adaptogenic Activity of l-Arginine Supplementation

In the present study, oral supplementation of L-arginine inrats was evaluated for its anti-stress and adaptogenic activityusing the cold (5°C)–hypoxia (428 mmHg)–restraint(C-H-R) animal model. A dose-dependent study of L-arginine wascarried out at doses of 12.5, 25.0, 50.0, 100.0, 200.0 and 500.0mg/kg body weight, administered orally 30 min prior to C-H-Rexposure. The time taken by the rat to attain a rectal temperatureof 23°C (T_rec 23°C) during C-H-R exposure and its recoveryto T_rec 37°C at normal atmospheric pressure and 32 ±1°C were used as biomarkers of anti-stress and adaptogenicactivity. Biochemical parameters related to lipid peroxidation,anti-oxidants, cell membrane permeability, nitric oxide andstress, with and without administration of the least effectiveL-arginine dose, were measured in rats on attaining T_rec 23°Cand T_rec 37°C. The least effective adaptogenic dose of L-argininewas 100.0 mg/kg body weight. The C-H-R exposure of control rats,on attaining T_rec 23°C, resulted in a significant increasein plasma malondialdehyde (MDA), blood lactate dehydrogenase(LDH) and a decrease in blood catalase (CAT) and plasma testosteronelevels. On recovery (T_rec 37°C) of control rats, there wasa further decrease in CAT and plasma testosterone, and an increasein LDH. L-Arginine supplementation resulted in a significantdecrease in plasma MDA, an increase in blood superoxide dismutase(SOD), CAT levels maintained at control values and a lower increasein LDH compared with controls (45.3 versus 58.5% and 21.5 versus105.2%) on attaining T_rec 23°C during C-H-R exposure andon recovery to T_rec 37°C. The results suggested that L-argininepossesses potent anti-stress activity during C-H-R exposureand recovery from C-H-R-induced hypothermia.     

Nourishing Yin and promoting blood circulation of TCM to treat hemorheologic disorder induced by diabetes mellitus in rats

Diabetes mellitus, DM, is commonly accompanied with variousstages of hemorheologic disturbances that are the main causesof the development of chronic DM. In this study, simple Chinesematerial medica [yang-yin jiang-tang preparation (YYJT)] wasgiven to alloxan-induced DM rats and analyzed to compare thechanges of fasting blood glucose (FBG), fasting insulin (FINS),hemorheologic parameters and insulin-like growth factor II (IGF-II)before and after administration. The results suggested thatYYJT can significantly downregulate FBG (P < 0.005), improveinsulin resistance and beta-cell secretion (P < 0.05), decreasewhole blood viscosity at low and high shear rates, gatheringof blood index test (GIT) and fibrinogen (FIB) (P < 0.05),and enlarge the function of IGF-II (P < 0.05). We concludedthat YYJT could prevent and treat hemorheologic disorder inDM rats by means of reducing glucose, improving insulin resistanceand elevating IGF-II.     

Indigofera suffruticosa: an alternative anticancer therapy

Indigofera suffruticosa Mill (Fabeceae) occurs in the Northeastcountryside and has intensive popular use in the treatment ofinfectious, inflammatory and other processes. The main aim ofthe present work was to investigate the cytotoxic and antitumoreffects of aqueous extracts of leaves of I. suffruticosa obtainedby infusion and maceration as well as to evaluate the toxicologicalproperties. Aqueous extracts did not exhibit cytotoxicity againstHEp-2 (human epidermoid cancer cell) cell lines by MTT method.From the aqueous extract by infusion, the toxicological assayshowed low order of toxicity. The antitumor effect of aqueousextracts by infusion (64.53%) and maceration (62.62%) againstsarcoma 180 in mice at a dose of 50 mg kg^–1 (intraperitoneally),based on low order of toxicity was comparable to the controlgroup, which showed 100% development. Considering the low orderof toxicity and that it is highly effective in inhibiting growthof solid tumors, the aqueous extracts of leaves of I. suffruticosamay be used as an alternative anticancer agent.     

Immunological and Psychological Benefits of Aromatherapy Massage

This preliminary investigation compares peripheral blood cellcounts including red blood cells (RBCs), white blood cells (WBCs),neutrophils, peripheral blood lymphocytes (PBLs), CD4⁺, CD8⁺and CD16⁺ lymphocytes, CD4⁺/CD8⁺ ratio, hematocrit, humoralparameters including serum interferon- and interleukin-6, salivarysecretory immunoglobulin A (IgA). Psychological measures includingthe State–Trait Anxiety Inventory (STAI) questionnaireand the Self-rating Depression Scale (SDS) between recipients(n = 11) of carrier oil massage and aromatherapy massage, whichincludes sweet almond oil, lavender oil, cypress oil and sweetmarjoram oil. Though both STAI and SDS showed a significantreduction (P < 0.01) after treatment with aromatherapy andcarrier massage, no difference between the aromatherapy andcontrol massage was observed for STAI and SDS. Aromatherapy,in contrast to control massage, did not significantly reduceRBC count or hematocrit. However, aromatherapy massage showeda significant (P > 0.05) increase in PBLs, possibly due toan increase in CD8⁺ and CD16⁺ lymphocytes, which had significantlyincreased post-treatment (P < 0.01). Consequently, the CD4⁺/CD8⁺ratio decreased significantly (P < 0.01). The paucity ofsuch differences after carrier oil massage suggests that aromatherapymassage could be beneficial in disease states that require augmentationof CD8⁺ lymphocytes. While this study identifies the immunologicalbenefits of aromatherapy massage, there is a need to validatethe findings prospectively in a larger cohort of patients.     

Adjuvant Ozonetherapy in Advanced Head and Neck Tumors: A Comparative Study

Advanced head and neck (H&N) tumors have a poor prognosis,and this is worsened by the occurrence of hypoxia and ischemiain the tumors. Ozonetherapy has proved useful in the treatmentof ischemic syndromes, and several studies have described apotential increase of oxygenation in tissues and tumors. Theaim of this prospective study was to evaluate the clinical effectof ozonetherapy in patients with advanced H&N cancer inthe course of their scheduled radiotherapy. Over a period of3 years, 19 patients with advanced H&N tumors who were undergoingtreatment in our department with non-standard fractionated radiotherapyplus oral tegafur. A group of 12 patients was additionally treatedwith intravenous chemotherapy before and/or during radiotherapy.In the other group of seven patients, systemic ozonetherapywas administered twice weekly during radiotherapy. The ozonetherapygroup was older (64 versus 54 years old, P = 0.006), with ahigher percentage of lymph node involvement (71% versus 8%,P = 0.019) and with a trend to more unfavorable tumor stage(57% versus 8% IVb + IVc stages, P = 0.073). However, therewas no significant difference in overall survival between thechemotherapy (median 6 months) and ozonetherapy (8 months) groups.Although these results have to be viewed with caution becauseof the limited number of patients, they suggest that ozonetherapycould have had some positive effect during the treatment ofour patients with advanced H&N tumors. The adjuvant administrationof ozonetherapy during the chemo–radiotherapy for thesetumors merits further research.     

Traditional and Modern Biomedical Prospecting: Part II-the Benefits: Approaches for a Sustainable Exploitation of Biodiversity (Secondary Metabolites and Biomaterials from Sponges)

The progress in molecular and cell biology has enabled a rationalexploitation of the natural resources of the secondary metabolitesand biomaterials from sponges (phylum Porifera). It could beestablished that these natural substances are superior for biomedicalapplication to those obtained by the traditional combinatorialchemical approach. It is now established that the basic structuraland functional elements are highly conserved from sponges tothe crown taxa within the Protostomia (Drosophila melanogasterand Caenorhabditis elegans) and Deuterostomia (human); therefore,it is obvious that the molecular etiology of diseases withinthe metazoan animals have a common basis. Hence, the major challengefor scientists studying natural product chemistry is to elucidatethe target(s) of a given secondary metabolite, which is perse highly active and selective. After this step, the potentialclinical application can be approached. The potential valueof some selected secondary metabolites, all obtained from spongesand their associated microorganisms, is highlighted. Examplesof compounds that are already in medical use (inhibition oftumor/virus growth [arabinofuranosyl cytosine and arabinofuranosyladenine]), or are being considered as lead structures (actingas cytostatic and anti-inflammatory secondary metabolites [avarol/avarone],causing induction of apoptosis [sorbicillactone]) or as prototypesfor the interference with metabolic pathways common in organismsranging from sponges to humans (modulation of pathways activatedby fungal components [aeroplysinin], inhibition of angiogenesis[2-methylthio-1,4-napthoquinone], immune modulating activity[FK506]) are discussed in this study. In addition, bioactiveproteins from sponges are listed (antibacterial activity [pore-formingprotein and tachylectin]). Finally, it is outlined that theskeletal elements—the spicules—serve as blueprintsfor new biomaterials, especially those based on biosilica, whichmight be applied in biomedicine. These compounds and biomaterialshave been isolated/studied by members of the German Center ofExcellence BIOTECmarin. The goal for the future is to successfullyintroduce some of these compounds in the treatment of humandiseases in order to raise the public awareness on the richnessand diversity of natural products, which should be sustainablyexploited for human benefit.     

An Overview of Bee Venom Acupuncture in the Treatment of Arthritis

Bee venom acupuncture (BVA), as a kind of herbal acupuncture,exerts not only pharmacological actions from the bioactive compoundsisolated from bee venom but also a mechanical function fromacupuncture stimulation. BVA is growing in popularity, especiallyin Korea, and is used primarily for pain relief in many kindsof diseases. We aimed to summarize and evaluate the availableevidence of BVA for rheumatoid arthritis and osteoarthritis.Computerized literature searches for experimental studies andclinical trials of BVA for arthritis were performed on the databasesfrom PUBMED, EMBASE and the Cochrane Library. In addition, twoleading Korean journals (The Journal of Korean Society for Acupunctureand Moxibustion and The Journal of Korean Oriental Medicine)were searched for relevant studies. The search revealed 67 studies,15 of which met our criteria. The anti-inflammation and analgesicactions of BVA were proved in various kinds of animal arthriticmodels. Two randomized controlled trials and three uncontrolledclinical trials showed that BVA was effective in the treatmentof arthritis. It is highly likely that the effectiveness ofBVA for arthritis is a promising area of future research. However,there is limited evidence demonstrating the efficacy of BVAin arthritis. Rigorous trials with large sample size and adequatedesign are needed to define the role of BVA for these indications.In addition, studies on the optimal dosage and concentrationof BVA are recommended for future trials.     

Comparative Electropharmacological Actions of Some Constituents from Ginkgo biloba Extract in Guinea-pig Ventricular Cardiomyocytes

Effects of the constituents from Ginkgo biloba extract (GBE)on the action potentials and the ionic currents in guinea pigventricular cardiomyocytes were investigated using whole-celland current-clamp techniques. The constituents, ginkgolidesA, B, C and quercetin, had depressant effects at 0.1–3µMon the action potential configuration. Ginkgolide A (1–3µM) prolonged the action potential (action potential duration:APD) at 75% and 90% repolarizations (APD₇₅ and APD₉₀). However,ginkgolides B and C at low concentrations prolonged APD, butat higher concentrations (>1 µM) shortened APD. Quercetinat 3 µM prolonged the APD, but not at the lower concentrations.These constituents also inhibited the V_max. The resting potentialwas unaffected. In voltage-clamp experiments, ginkgolides Aand B (0.1–3 µM) markedly and concentration-dependentlyincreased the Ca²⁺ current (I_Ca) and the delayed rectifier K⁺current (I_K), and decreased the inwardly rectifying K⁺ current(I_K1). On the other hand, ginkgolide C failed to affect theI_Ca but increased the I_K by 14.0 ± 2.3% (n = 6, P <0.05) at 1 µM. Quercetin inhibited I_Ca, and enhanced I_Kbut decreased I_K1. These responses to the constituents werealmost reversible (80–90% of control) after a 10- to 20-minwashout. These results indicate that even at acute administrations,these constituents produce the effective actions on the APDand the underlying ionic currents in cardiomyocytes. Each constituentdoes not exhibit a uniform response, although GBE acts as anet.