Butylidenephthalide Blocks Potassium Channels and Enhances Basal Tension in Isolated Guinea-Pig Trachea

Butylidenephthalide (Bdph, 30~300 μM), a constituent ofLigusticum chuanxiongHort., significantly enhanced tension in isolated guinea-pig trachea. In this study, we investigate the mechanism(s) of Bdph-induced contraction in the tissue. Isolated trachea was bathed in 5 mL of Krebs solution containing indomethacin (3 μM), and its tension changes were isometrically recorded. Cromakalim (3 μM), an ATP-dependent K+channel opener, significantly antagonized the Bdph-induced enhancement of baseline tension. Bdph (300 μM) also significantly antagonized cromakalim-induced relaxation. Bdph (300 μM) did not significantly influence the antagonistic effects of glibenclamide (GBC, 1 μM) and tetraethylammonium (TEA, 8 mM) against the cromakalim-induced relaxation. However, Bdph (300 μM) and 4-aminopiridine (4-AP, 5 mM), a blocker of Kv1 family of K+channels, in combination significantly rightward shifted the log concentration-relaxation curve of cromakalim. The antagonistic effect of the combination almost equals the sum of the individual effects of Bdph and 4-AP, suggesting that the antagonistic mechanism of Bdph may be similar to that of 4-AP. All calcium channel blockers influenced neither the baseline tension nor antagonistic effect of Bdph against cromakalim. In conclusion, Bdph may be similar to 4-AP, a blocker of Kv1 family of K+channels, to enhance the baseline tension of guinea-pig trachea.

Download Full-text

Neutral/negative α1-AR antagonists and calcium channel blockers at comparison in functional tests on guinea-pig smooth muscle and myocardium

Pharmacological Reports ◽

10.1016/j.pharep.2018.10.007 ◽

2019 ◽

Vol 71 (1) ◽

pp. 128-132 ◽

Cited By ~ 2

Author(s):

Matteo Micucci ◽

Alberto Chiarini ◽

Roberta Budriesi

Keyword(s):

Smooth Muscle ◽

Guinea Pig ◽

Calcium Channel ◽

Calcium Channel Blockers ◽

Channel Blockers ◽

Functional Tests

Download Full-text

Increased Efficacy of Zinc Complexes With Picolinic and Aspartic Acids Against Herpes Simplex Virus (HSV) Infection When Combined With the Pavine Alkaloid (-)-Thalimonine

Metal-Based Drugs ◽

10.1155/mbd.2000.257 ◽

2000 ◽

Vol 7 (5) ◽

pp. 257-263 ◽

Cited By ~ 1

Author(s):

Assia L. Angelova ◽

Tatiana L. Varadinova

Keyword(s):

Herpes Simplex ◽

Cultured Cells ◽

Antagonistic Effect ◽

Zinc Complexes ◽

Individual Effects ◽

Infected Cells ◽

The Individual ◽

Simplex Virus ◽

Key Steps ◽

Hsv 1

Complexes of zinc with picolinic and aspartic acids inhibit key steps of HSV-1 replication affecting different virus-specific targets. As was recently demonstrated by us, the pavine alkaloid (-)-thalimonine irreversibly inhibits HSV-1 infection in cultured cells. The aim of the present study was the evaluation of the combined effect of zinc complexes and (-)-thalimonine on uninfected and HSV-1 infected cells. The data obtained have shown that zinc complexes and the alkaloid exert decreased cytotoxicity (antagonistic effect) and significantly increased anti-HSV-1 activity (synergistic effect) when applied in dual chess-board combinations as compared to the individual effects of compounds tested. These combinations are also effective against the infection caused by a resistant to acyclovir (ACV) HSV-1 mutant and the effect has been recognised as synergistic.

Download Full-text

Evidence for a Direct Effect on Vascular Permeability of Platelet-Activating Factor Induced Hemoconcentration in the Guinea Pig

Thrombosis and Haemostasis ◽

10.1055/s-0038-1660126 ◽

1985 ◽

Vol 54 (04) ◽

pp. 756-759 ◽

Cited By ~ 24

Author(s):

Dean A Handley ◽

Mark L Lee ◽

Robert N Saunders

Keyword(s):

Guinea Pig ◽

Vascular Permeability ◽

Calcium Channel Blockers ◽

Platelet Activating Factor ◽

Channel Blockers ◽

Heptanoic Acid ◽

Thromboxane Synthetase ◽

Specific Antagonist ◽

Protein Rich ◽

Prior Administration

SummaryThe ability of synthetic platelet-activating factor (PAF) given intravenously to produce loss (extravasation) of protein rich plasma (resulting in hemoconcentration) has been examined using guinea pigs. Hemoconcentration induced by PAF was not prevented by prior administration of inhibitors of thromboxane synthetase (7-(3-pyridyl)heptanoic acid, UK-37,248-01), PGI2, aspirin, indomethacin or antiserum induced thrombocytopenia. Calcium channel blockers (nifedipine, verapamil, diethyl-amino octyltrimethoxybenzoate, diltiazem), antihistamines (pyrilamine, cimetidine, diphenhydramine), or the elevator of cAMP IBMX were ineffective in blocking PAF-induced hemoconcentration. In contrast, CV-3988, reported to be a specific antagonist to PAF, was 98% inhibitory of PAF extravasation when given i. a. at 3.5 mg/kg. The ED50 was 0.14 mg/kg I. A. and 15 mg/kg p.o. against 75 ng/kg PAF. These data suggest that PAF-induced hemoconcentration involves receptor mediated alterations of vascular permeability that are inhibited by a specific PAF antagonist.

Download Full-text

Picrotoxin-induced epileptic activity in hippocampal and neocortical slices (guinea pig): suppression by organic calcium channel blockers

Brain Research ◽

10.1016/s0006-8993(09)90017-8 ◽

1994 ◽

Vol 658 (1-2) ◽

pp. 119-126 ◽

Cited By ~ 19

Author(s):

H. Straub ◽

R. Köhling ◽

E.-J. Speckmann

Keyword(s):

Guinea Pig ◽

Calcium Channel ◽

Calcium Channel Blockers ◽

Epileptic Activity ◽

Channel Blockers

Download Full-text

NiCl2 and Amiloride Induce Spreading Depression in Guinea Pig Hippocampal Slices

Cephalalgia ◽

10.1111/j.1468-2982.2000.00124.x ◽

2000 ◽

Vol 20 (8) ◽

pp. 740-747 ◽

Cited By ~ 12

Author(s):

A Gorji ◽

D Scheller ◽

F Tegtmeier ◽

R Köhling ◽

H Straub ◽

...

Keyword(s):

Guinea Pig ◽

Calcium Channel Blockers ◽

Response Curve ◽

Spreading Depression ◽

Hippocampal Slices ◽

Nmda Antagonist ◽

Calcium Oscillations ◽

Channel Blockers ◽

Dc Potential ◽

Concentration Response Curve

Spreading depressions (SD) occur in association with ischaemia, epilepsy and migraine. Intracellular calcium oscillations have been suggested to be involved in the generation and propagation of SD. The present study was performed to study the mechanism of conditioning guinea pig hippocampal slices by the T-type calcium channel blockers NiCl2 and amiloride. SD-like fluctuations of DC potential were recorded by inserting microelectrodes into the CA1 and CA3 regions. The SD occurrence was significantly greater with 10 µmol/ l NiCl2 as well as with 25 and 50 µmol/ l amiloride than with other concentrations of these substances. The concentration response curve was inversely U-shaped with the maximum repetition rates of SDs being achieved at 10 µmol/ l NiCl2 as well as at 25 and 50 µmol/ l amiloride. SD occurrence could be completely blocked by the NMDA antagonist APV (10 µmol/ l) in all cases. These data demonstrate that modulation of the Ca2+ dynamics conditioned guinea pig hippocampal slices and increased their susceptibility to generate SD.

Download Full-text

Characterization of selective Calcium-Release Activated Calcium channel blockers in mast cells and T-cells from human, rat, mouse and guinea-pig preparations

European Journal of Pharmacology ◽

10.1016/j.ejphar.2013.02.022 ◽

2013 ◽

Vol 704 (1-3) ◽

pp. 49-57 ◽

Cited By ~ 31

Author(s):

Louise V. Rice ◽

Heather J. Bax ◽

Linda J. Russell ◽

Victoria J. Barrett ◽

Sarah E. Walton ◽

...

Keyword(s):

T Cells ◽

Mast Cells ◽

Guinea Pig ◽

Calcium Channel ◽

Calcium Channel Blockers ◽

Calcium Release ◽

Channel Blockers

Download Full-text

Effect of Blends of Benzotriazole and Thiourea on the Anodic Dissolution of Copper

Adsorption Science & Technology ◽

10.1260/026361702320644761 ◽

2002 ◽

Vol 20 (5) ◽

pp. 485-494 ◽

Cited By ~ 5

Author(s):

E.A. Ashour ◽

H.S. Hegazy ◽

B.G. Ateya

Keyword(s):

Free Energy ◽

Anodic Dissolution ◽

Hydrogen Sulphide ◽

Copper Surface ◽

Antagonistic Effect ◽

Adsorption Behaviour ◽

Free Energy Of Adsorption ◽

Antagonistic Effects ◽

Low Concentrations ◽

The Individual

The blending of benzotriazole (BTAH) and thiourea (TU) was shown to exert synergistic or antagonistic effects on the anodic dissolution of copper at pH ≈ 1.8 depending on their concentrations in the blend. While synergism was observed in blends with low concentrations of TU and BTAH, antagonism was observed in blends containing higher, i.e. ≥ 10−2 M, concentrations of TU to an extent which increased with the concentration of TU. The antagonistic effect of TU was discussed in the light of its tendency to produce hydrogen sulphide which promotes the anodic dissolution of copper. Analysis of the adsorption behaviour of the individual compounds using the Langmuir isotherm revealed stronger interaction of the copper surface with BTAH than with TU, as judged by free energy of adsorption values of −18.8 and −8.7 kJ/mol for BTAH and TU, respectively.

Download Full-text