Biomaterial Database

Cardiovascular effects of an organophosphate toxin isolated from Ptychodiscus brevis. 1997

P K Mazumder, and A K Gupta, and M P Kaushik, and D Kumar, and S N Dube

Defence Research and Development Establishment, Gwalior, India.

The dose-dependent hypotensive and bradycardic effects induced by an ichthyotoxic organophosphate compound isolated from the marine dinoflagellate Ptychodiscus brevis were studied. These effects were not antagonized by atropine, but potentiated by alpha-adrenoceptor blocker and hexamethonium. The toxin abolished the vasopressor effect elicited by phenylephrine, indicating an alpha-adrenergic blocking activity. The cardiovascular depressor responses were antagonized by tetraethylammonium while blockade of cholinergic and histaminergic receptors or inhibition of prostaglandin synthesis failed to modify these effects. The results indicate that the cardiovascular depressor effects of the toxin are probably mediated through alpha-adrenergic and ganglionic blockade accompanied by modulation of potassium channel activity.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008387	Marine Toxins	Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES.	Marine Biotoxins,Phycotoxins
D009388	Neostigmine	A cholinesterase inhibitor used in the treatment of myasthenia gravis and to reverse the effects of muscle relaxants such as gallamine and tubocurarine. Neostigmine, unlike PHYSOSTIGMINE, does not cross the blood-brain barrier.	Synstigmin,Neostigmine Bromide,Neostigmine Methylsulfate,Polstigmine,Proserine,Prostigmin,Prostigmine,Prozerin,Syntostigmine,Bromide, Neostigmine,Methylsulfate, Neostigmine
D009943	Organophosphorus Compounds	Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.	Organophosphorus Compound,Organopyrophosphorus Compound,Organopyrophosphorus Compounds,Compound, Organophosphorus,Compound, Organopyrophosphorus,Compounds, Organophosphorus,Compounds, Organopyrophosphorus
D010975	Platelet Aggregation Inhibitors	Drugs or agents which antagonize or impair any mechanism leading to blood platelet aggregation, whether during the phases of activation and shape change or following the dense-granule release reaction and stimulation of the prostaglandin-thromboxane system.	Antiaggregants, Platelet,Antiplatelet Agent,Antiplatelet Agents,Antiplatelet Drug,Blood Platelet Aggregation Inhibitor,Blood Platelet Antagonist,Blood Platelet Antiaggregant,PAR-1 Antagonists,Platelet Aggregation Inhibitor,Platelet Antagonist,Platelet Antagonists,Platelet Antiaggregant,Platelet Antiaggregants,Platelet Inhibitor,Protease-Activated Receptor-1 Antagonists,Antiplatelet Drugs,Blood Platelet Aggregation Inhibitors,Blood Platelet Antagonists,Blood Platelet Antiaggregants,Platelet Inhibitors,Agent, Antiplatelet,Aggregation Inhibitor, Platelet,Antagonist, Blood Platelet,Antagonist, Platelet,Antiaggregant, Blood Platelet,Antiaggregant, Platelet,Drug, Antiplatelet,Inhibitor, Platelet,Inhibitor, Platelet Aggregation,PAR 1 Antagonists,Platelet Antagonist, Blood,Platelet Antiaggregant, Blood,Protease Activated Receptor 1 Antagonists
D011224	Prazosin	A selective adrenergic alpha-1 antagonist used in the treatment of HEART FAILURE; HYPERTENSION; PHEOCHROMOCYTOMA; RAYNAUD DISEASE; PROSTATIC HYPERTROPHY; and URINARY RETENTION.	Furazosin,Minipress,Pratsiol,Prazosin HCL,Prazosin Hydrochloride,HCL, Prazosin,Hydrochloride, Prazosin
D002319	Cardiovascular System	The HEART and the BLOOD VESSELS by which BLOOD is pumped and circulated through the body.	Circulatory System,Cardiovascular Systems,Circulatory Systems
D002800	Cholinesterase Inhibitors	Drugs that inhibit cholinesterases. The neurotransmitter ACETYLCHOLINE is rapidly hydrolyzed, and thereby inactivated, by cholinesterases. When cholinesterases are inhibited, the action of endogenously released acetylcholine at cholinergic synapses is potentiated. Cholinesterase inhibitors are widely used clinically for their potentiation of cholinergic inputs to the gastrointestinal tract and urinary bladder, the eye, and skeletal muscles; they are also used for their effects on the heart and the central nervous system.	Acetylcholinesterase Inhibitor,Acetylcholinesterase Inhibitors,Anti-Cholinesterase,Anticholinesterase,Anticholinesterase Agent,Anticholinesterase Agents,Anticholinesterase Drug,Cholinesterase Inhibitor,Anti-Cholinesterases,Anticholinesterase Drugs,Anticholinesterases,Cholinesterase Inhibitors, Irreversible,Cholinesterase Inhibitors, Reversible,Agent, Anticholinesterase,Agents, Anticholinesterase,Anti Cholinesterase,Anti Cholinesterases,Drug, Anticholinesterase,Drugs, Anticholinesterase,Inhibitor, Acetylcholinesterase,Inhibitor, Cholinesterase,Inhibitors, Acetylcholinesterase,Inhibitors, Cholinesterase,Inhibitors, Irreversible Cholinesterase,Inhibitors, Reversible Cholinesterase,Irreversible Cholinesterase Inhibitors,Reversible Cholinesterase Inhibitors
D002927	Cimetidine	A histamine congener, it competitively inhibits HISTAMINE binding to HISTAMINE H2 RECEPTORS. Cimetidine has a range of pharmacological actions. It inhibits GASTRIC ACID secretion, as well as PEPSIN and GASTRIN output.	Altramet,Biomet,Biomet400,Cimetidine HCl,Cimetidine Hydrochloride,Eureceptor,Histodil,N-Cyano-N'-methyl-N''-(2-(((5-methyl-1H-imidazol-4-yl)methyl)thio)ethyl)guanidine,SK&F-92334,SKF-92334,Tagamet,HCl, Cimetidine,Hydrochloride, Cimetidine,SK&F 92334,SK&F92334,SKF 92334,SKF92334
D004141	Dinoflagellida	Flagellate EUKARYOTES, found mainly in the oceans. They are characterized by the presence of transverse and longitudinal flagella which propel the organisms in a rotating manner through the water. Dinoflagellida were formerly members of the class Phytomastigophorea under the old five kingdom paradigm.	Amphidinium,Dinoflagellata,Dinophyceae,Dinophycidae,Dinophyta,Dinophytes,Gambierdiscus toxicus,Gonyaulax,Gymnodinium,Peridinium,Pyrrhophyta,Pyrrophyta,Dinoflagellates