We investigated the effect of alpha-adrenergic and cholinergic receptor agonists on Ca2+ current in adult rat trigeminal ganglion neurons using whole-cell patch clamp methods. The application of acetylcholine, carbachol, and oxotremorine (50 muM each) produced a rapid and reversible reduction of the Ca2+ current by 17+/-6%, 19+/-3% and 18+/-4%, respectively. Atropine, a muscarinic antagonist, blocked carbachol-induced Ca2+ current inhibition to 3 +/- 1%. Norepinephrine (50 muM) reduced Ca2+ current by 18 +/- 2%, while clonidine (50 muM), an alpha2-adrenergic receptor agonist, inhibited Ca2+ current by only 4 +/- 1%. Yohimbine, an alpha2-adrenergic receptor antagonist, did not block the inhibitory effect of norepinephrine on Ca2+ current, whereas prazosin, an alpha1-adrenergic receptor antagonist, attenuated the inhibitory effect of norepinephrine on Ca2+ current to 6 +/- 1%. This pharmacology contrasts with alpha2-adrenergic receptor modulation of Ca2+ channels in rat sympathetic neurons, which is sensitive to clonidine and blocked by yohimbine. Our data suggest that the modulation of voltage dependent Ca2+ channel by norepinephrine is mediated via an alpha1-adrenergic receptor. Pretreatment with pertussis toxin (250 ng/ml) for 16 h greatly reduced norepinephrine- and carbachol-induced Ca2+ current inhibition from 17 +/- 3% and 18 +/- 3% to 2 +/- 1% and 2 +/- 1%, respectively. These results demonstrate that norepinephrine, through an alpha1-adrenergic receptor, and carbachol, through a muscarinic receptor, inhibit Ca2+ currents in adult rat trigeminal ganglion neurons via pertussis toxin sensitive GTP-binding proteins.
Acetylcholine ; Adult ; Animals ; Atropine ; Carbachol ; Clonidine ; GTP-Binding Proteins ; Humans ; Neurons ; Norepinephrine ; Oxotremorine ; Pertussis Toxin ; Pharmacology ; Prazosin ; Rats ; Receptors, Muscarinic ; Trigeminal Ganglion ; Yohimbine

PURPOSE: Though it has been well known that the autologous vein graft is conduit of choice for infragenicular leg artery bypass, it is still less clear for above-knee femoro-popliteal artery bypass. We attempted to evaluate the outcomes of reversed saphenous vein graft in comparison with polytetrafluoroethylene (PTFE) graft in above-knee femoro-popliteal bypasses for the patients with chronic arterial occlusive disease. METHOD: In a period of 7 years and 9 months, 108 above-knee femoro-popliteal bypasses were performed in 96 patients (91 male, 5 female, mean age 67.3 years). The indications for bypass operation were short distance claudication in 54 (50%), rest pain in 36 (33%), and toe, foot ulcer or gangrene in 18 (17%) limbs. As bypass conduit, autologous reversed saphenous vein was used in 67 limbs, and PTFE graft in 41 limbs. We compared early (<30 days) postoperative complications, primary patency rates of grafts, and late outcomes of the limbs with proven graft occlusion between 2 patients groups (vein graft group vs. PTFE graft group). Primary cumulative graft patency rate were determined by Kaplan Meier method and compared them with log-rank test. RESULT: Early postoperative complications were not significantly different between two groups. During the follow-up period, 20 (18.5%) grafts were lost to follow-up and 14 patients were dead. Primary cumulative patency rates at 1, 3, 5 years were 97.44 +/- 2.53%, 91.11 +/- 4.94%, and 75.92 +/- 14.46% for vein grafts and 81.76 +/- 7.49%, 36.15 +/- 13.42, and 36.15 +/- 13.42% for PTFE grafts respectively. CONCLUSION: In the patients underwent autologous vein graft for above-knee femoro-popliteal bypass, we experienced significantly better long-term patency, less serious surgical complication and less severe recurrent ischemic symptom after graft occlusion than in patients with PTFE graft.
Arterial Occlusive Diseases ; Arteries ; Extremities ; Female ; Follow-Up Studies ; Foot Ulcer ; Gangrene ; Humans ; Leg ; Lost to Follow-Up ; Male ; Polytetrafluoroethylene ; Postoperative Complications ; Saphenous Vein ; Toes ; Transplants* ; Veins*

Contribution of prostaglandins D2, E2 and I2 (PGD2, PGE2 and PGI2) on the regulation of ATP-sensitive K+ channel (KATP channel) was investigated in isolated single rat ventricular cardiac myocytes using the patch clamp technique. PGD2, PGE2 and PGI2 did not affect KATP channel activity in the inside-out patch, but increased channel activity in a dose-dependent manner when the channel activities were attenuated by the administration of 100 muM ATP to the internal solution in the inside-out patch. Channel activations by the prostaglandins were abolished by 50 muM glibenclamide, a KATP channel blocker. Dose-response curves of relative channel activity against the ATP concentrations of internal solution in the inside-out patch were shifted to the right in the presence of those three prostaglandins. The rank order of the channel stimulatory potencies (as IC50 for ATP) calculated from the dose-response curves were PGI2 < PGD2 < PGE2. Conductance of the channel was not changed by those three prostaglandins. In conclusion, we suggest that prostaglandins D2, E2 and I2 are involved in the regulation of KATP channel activity in certain circumstances, and that those three prostaglandins may cause myocardial relaxation by opening KATP channels, thus protecting the heart from ischema.
Adenosine Triphosphate ; Animals ; Dinoprostone ; Epoprostenol ; Glyburide ; Heart ; Inhibitory Concentration 50 ; KATP Channels ; Myocytes, Cardiac* ; Prostaglandin D2 ; Prostaglandins* ; Rats* ; Relaxation

Along with the multiple neuroprotective effect, recent studies suggest that gintonin might increase the blood brain barrier permeability. We evaluated the effect of gintonin on the vascular permeability changes in different brain segments, using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). In this 8-week, randomized, open label pilot study, ten participants with subjective memory impairment but preserved cognitive function assigned to gintonin-enriched fraction (GEF) 300 mg/day or placebo groups. Korean versions of the Alzheimer's disease assessment scale (ADAS-K) and DCE-MRI parameters including Ktrans and Vp in different brain segments were evaluated at baseline and at 8 weeks after treatment. Nine participants completed the study protocol. No adverse events occurred during the observation period for 8 weeks in both groups. Following gintonin administration, increment trends of the brain permeability that did not reach a statistical significance were observed in the left hippocampus (Ktrans and Vp , both, p = 0.062), left thalamus and in left putamen (Ktrans , p = 0.062), and left insula and right amygdala (Vp , p = 0.062), but not in the control placebo group. The increment of the Ktrans value in the left thalamus from the baseline was highly correlated with the change of the ADAS scores (r = −0.900, p = 0.037). Gintonin might enhance the blood-brain barrier (BBB) permeability in the brain structures involved in cognitive functions. Further efficacy exploration for the synergistic effect of gintonin's BBB permeability enhancement to its other cognitive enhancing mechanisms are warranted.

PURPOSE: Ginseng has been used throughout the Far East, including Korea and China, as a tonic and restorative agent to maintain physical vitality. The main pharmacoactive molecules of ginseng are ginsenosides. The present study was designed to investigate whether ginsenosides relax rabbit vaginal smooth muscle and whether this effect is modulated by nitric oxide(NO) and the cGMP pathway. MATERIALS AND METHODS: Strips of rabbit vagina were mounted in organ chambers to measure isometric tension. The strips were contracted with phenylephrine(5 X 10(-5) M), and the responses to acetylcholine, nitric oxide inhibitor, and ginsenosides were examined. The cGMP content of the strips was measured by radioimmunoassay after various doses of ginsenosides. RESULTS: Ginsenosides(100~500microgram/mL) relaxed vaginal smooth muscle in a dose-dependent manner(5~25%). Acetylcholine-induced relaxation was significantly increased in the presence of ginsenosides(100, 200microgram/mL)(p<0.05). The relaxation effect of ginsenosides was inhibited by L-NAME(10(-4) M), but the difference was not statistically significant(p>0.05). Ginsenosides(400microgram/mL for 7 min) increased the accumulation of cGMP. CONCLUSIONS: These data suggest that ginsenosides have a relaxing effect on rabbit vaginal smooth muscle. This effect is at least in part mediated by the NO-cGMP pathway.
Acetylcholine ; China ; Far East ; Ginsenosides* ; Korea ; Muscle, Smooth* ; Nitric Oxide ; Panax ; Radioimmunoassay ; Relaxation* ; Vagina

Quercetin mainly exists in the skin of colored fruits and vegetables as one of flavonoids. Recent studies show that quercetin, like other flavonoids, has diverse pharmacological actions. However, relatively little is known about quercetin effects in the regulations of ligand-gated ion channels. In the previous reports, we have shown that quercetin regulates subsets of homomeric ligand-gated ion channels such as glycine, 5-HT3A and alpha7 nicotinic acetylcholine receptors. In the present study, we examined quercetin effects on heteromeric neuronal alpha3beta4 nicotinic acetylcholine receptor channel activity expressed in Xenopus oocytes after injection of cRNA encoding bovine neuronal alpha3 and beta4 subunits. Treatment with acetylcholine elicited an inward peak current (IACh) in oocytes expressing alpha3beta4 nicotinic acetylcholine receptor. Co-treatment with quercetin and acetylcholine inhibited IACh in oocytes expressing alpha3beta4 nicotinic acetylcholine receptors. The inhibition of IACh by quercetin was reversible and concentration-dependent. The half-inhibitory concentration (IC50) of quercetin was 14.9+/-0.8 microM in oocytes expressing alpha3beta4 nicotinic acetylcholine receptor. The inhibition of IACh by quercetin was voltage-independent and non-competitive. These results indicate that quercetin might regulate alpha3beta4 nicotinic acetylcholine receptor and this regulation might be one of the pharmacological actions of quercetin in nervous systems.
Acetylcholine ; Flavonoids ; Fruit ; Glycine ; Ligand-Gated Ion Channels ; Nervous System ; Neurons ; Oocytes ; Quercetin ; Receptors, Nicotinic ; RNA, Complementary ; Skin ; Social Control, Formal ; Vegetables ; Xenopus

Resveratrol is a phytoalexin found in grapes, red wine, and berries. Resveratrol has been known to have many beneficial health effects, such as anti-cancer, neuroprotective, anti-inflammatory, and life-prolonging effects. However, relatively little is known about the effects of resveratrol on the regulation of ligand-gated ion channels. We have previously reported that resveratrol regulates subsets of homomeric ligand-gated ion channels such as those of 5-HT3A receptors. The gamma-aminobutyric acidC (GABAC) receptor is mainly expressed in retinal bipolar cells and plays an important role in visual processing. In the present study, we examined the effects of resveratrol on the channel activity of homomeric GABAC receptor expressed in Xenopus oocytes injected with cRNA encoding human GABAC rho subunits. Our data show that the application of GABA elicits an inward peak current (IGABA) in oocytes that express the GABAC receptor. Resveratrol treatment had no effect on oocytes injected with H2O or with GABAC receptor cRNA. Co-treatment with resveratrol and GABA inhibited IGABA in oocytes with GABAC receptors. The inhibition of IGABA by resveratrol was in a reversible and concentration-dependent manner. The IC50 of resveratrol was 28.9+/-2.8 microM in oocytes expressing GABAC receptor. The inhibition of IGABA by resveratrol was in voltage-independent and non-competitive manner. These results indicate that resveratrol might regulate GABAC receptor expression and that this regulation might be one of the pharmacological actions of resveratrol on the nervous system.
Fruit ; gamma-Aminobutyric Acid ; Humans ; Inhibitory Concentration 50 ; Ligand-Gated Ion Channels ; Nervous System ; Oocytes ; Receptors, GABA ; Retinal Bipolar Cells ; RNA, Complementary ; Sesquiterpenes ; Stilbenes ; Vitis ; Wine ; Xenopus

The calcium-activated K+ (BKCa) channel is one of the potassium-selective ion channels that are present in the nervous and vascular systems. Ca2+ is the main regulator of BKCa channel activation. The BKCa channel contains two high affinity Ca2+ binding sites, namely, regulators of K+ conductance, RCK1 and the Ca2+ bowl. Lysophosphatidic acid (LPA, 1-radyl-2-hydroxy-sn-glycero-3-phosphate) is one of the neurolipids. LPA affects diverse cellular functions on many cell types through G protein-coupled LPA receptor subtypes. The activation of LPA receptors induces transient elevation of intracellular Ca2+ levels through diverse G proteins such as Galphaq/11, Galphai, Galpha12/13, and Galphas and the related signal transduction pathway. In the present study, we examined LPA effects on BKCa channel activity expressed in Xenopus oocytes, which are known to endogenously express the LPA receptor. Treatment with LPA induced a large outward current in a reversible and concentration-dependent manner. However, repeated treatment with LPA induced a rapid desensitization, and the LPA receptor antagonist Ki16425 blocked LPA action. LPA-mediated BKCa channel activation was also attenuated by the PLC inhibitor U-73122, IP3 inhibitor 2-APB, Ca2+ chelator BAPTA, or PKC inhibitor calphostin. In addition, mutations in RCK1 and RCK2 also attenuated LPA-mediated BKCa channel activation. The present study indicates that LPA-mediated activation of the BKCa channel is achieved through the PLC, IP3, Ca2+, and PKC pathway and that LPA-mediated activation of the BKCa channel could be one of the biological effects of LPA in the nervous and vascular systems.
Binding Sites ; Egtazic Acid ; Estrenes ; GTP-Binding Proteins ; Ion Channels ; Isoxazoles ; Lysophospholipids ; Naphthalenes ; Oocytes ; Potassium ; Potassium Channels ; Propionates ; Pyrrolidinones ; Receptors, Lysophosphatidic Acid ; Signal Transduction ; Xenopus

We studied the effects of ginseng protopanaxadiol (PD) and protopanaxatriol (PT) saponins on the analgesia using several pain tests such as writhing, formalin, and tail-flick test. Using mouse, pretreatment of PD or PT saponins (i.p.) induced inhibition of abdominal constrictions caused by 0.9% acetic acid administration (i.p.). The AD-50 was around 27 (17-43) mg/kg for PD and 13.5 (3-61) mg/kg for PT saponins in writhing test. Both PD and PT saponins also showed the inhibition of bitings and lickings of hindpaw after administration of 1% formalin. In particular, both PD and PT saponins showed analgesic effects on second phase of pain. The AD-50 was 44.5 (26-76) mg/kg for PD and 105 (55-200) mg/kg for PT saponins in second phase of formalin test. For first phase pain inhibition by PD or PT saponins, they were required higher concentrations. However, PD saponins showed weak analgesic effects in tail-flick test with high concentration. In conclusion, we found that both PD and PT saponins have the analgesic effects in writhing test and second phase of pain in formalin test. These results suggest that both PD and PT saponins inhibit neurogenic or tonic pain rather than acute pain.
Acetic Acid ; Acute Pain ; Analgesia ; Animals ; Constriction ; Formaldehyde ; Mice ; Pain Measurement ; Panax* ; Saponins

Background and Objectives: The relationship between the hospital percutaneous coronary intervention (PCI) volumes and the in-hospital clinical outcomes of patients with acute myocardial infarction (AMI) remains the subject of debate. This study aimed to determine whether the in-hospital clinical outcomes of patients with AMI in Korea are significantly associated with hospital PCI volumes. Methods: We selected and analyzed 17,121 cases of AMI, that is, 8,839 cases of non-ST-segment elevation myocardial infarction and 8,282 cases of ST-segment elevation myocardial infarction, enrolled in the 2014 Korean percutaneous coronary intervention (K-PCI) registry. Patients were divided into 2 groups according to hospital annual PCI volume, that is, to a high-volume group (≥400/year) or a low-volume group (<400/year). Major adverse cardiovascular and cerebrovascular events (MACCEs) were defined as composites of death, cardiac death, non-fatal myocardial infarction (MI), stent thrombosis, stroke, and need for urgent PCI during index admission after PCI. Results: Rates of MACCE and non-fatal MI were higher in the low-volume group than in the high-volume group (MACCE: 10.9% vs. 8.6%, p=0.001; non-fatal MI: 4.8% vs. 2.6%, p=0.001, respectively). Multivariate regression analysis showed PCI volume did not independently predict MACCE. Conclusions Hospital PCI volume was not found to be an independent predictor of in-hospital clinical outcomes in patients with AMI included in the 2014 K-PCI registry.