Biomaterial Database

Effects of prostanoids on isolated feline cerebral arteries. II. Roles of extra- and intracellular calcium for the prostaglandin F2 alpha-induced contraction. 1984

T K Uski, and K E Andersson

The roles of extra- and intracellular calcium for the contractile effects of PGF2 alpha in the feline basilar artery (BA) were investigated. Comparisons were made with contractions induced by K+ and noradrenaline (NA). Addition of nifedipine to PGF2 alpha- or K+ (124 mM)-contracted arteries resulted in an incomplete relaxation, whereas NA-contracted vessels were completely relaxed. Incubation of the preparations in a calcium-free medium containing 10(-5) M EGTA for 5-10 min almost abolished contractions induced by K+ and NA. In contrast, 63% of the response to PGF2 alpha remained after pretreatment of the arteries in a calcium-free solution for 40 min; PGF2 alpha produced a biphasic contraction in 17 out of 20 preparations consisting of a rapidly developing initial phase followed by a second increase in tension after 1-6 min. The second phase was absent if the EGTA-concentration was increased to 10(-4) M, or if the arteries were pre-treated with nifedipine. After incubation of the arteries in a calcium-free medium for 40-120 min and K+-depolarization, re-addition of calcium elicited contractions at lower concentrations in the presence of PGF2 alpha than in controls. The results suggest that PGF2 alpha-induced contractions in the feline BA are considerably less dependent on extracellular calcium than contractions evoked by K+ or NA. PGF2 alpha appears to be able to release calcium from two cellular stores, and may also promote calcium influx through the cell membrane.

UI	MeSH Term	Description	Entries
D007473	Ion Channels	Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.	Membrane Channels,Ion Channel,Ionic Channel,Ionic Channels,Membrane Channel,Channel, Ion,Channel, Ionic,Channel, Membrane,Channels, Ion,Channels, Ionic,Channels, Membrane
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009131	Muscle, Smooth, Vascular	The nonstriated involuntary muscle tissue of blood vessels.	Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D009543	Nifedipine	A potent vasodilator agent with calcium antagonistic action. It is a useful anti-anginal agent that also lowers blood pressure.	Adalat,BAY-a-1040,Bay-1040,Cordipin,Cordipine,Corinfar,Fenigidin,Korinfar,Nifangin,Nifedipine Monohydrochloride,Nifedipine-GTIS,Procardia,Procardia XL,Vascard,BAY a 1040,BAYa1040,Bay 1040,Bay1040,Monohydrochloride, Nifedipine,Nifedipine GTIS
D009638	Norepinephrine	Precursor of epinephrine that is secreted by the ADRENAL MEDULLA and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the LOCUS CERULEUS. It is also found in plants and is used pharmacologically as a sympathomimetic.	Levarterenol,Levonorepinephrine,Noradrenaline,Arterenol,Levonor,Levophed,Levophed Bitartrate,Noradrenaline Bitartrate,Noradrénaline tartrate renaudin,Norepinephrin d-Tartrate (1:1),Norepinephrine Bitartrate,Norepinephrine Hydrochloride,Norepinephrine Hydrochloride, (+)-Isomer,Norepinephrine Hydrochloride, (+,-)-Isomer,Norepinephrine d-Tartrate (1:1),Norepinephrine l-Tartrate (1:1),Norepinephrine l-Tartrate (1:1), (+,-)-Isomer,Norepinephrine l-Tartrate (1:1), Monohydrate,Norepinephrine l-Tartrate (1:1), Monohydrate, (+)-Isomer,Norepinephrine l-Tartrate (1:2),Norepinephrine l-Tartrate, (+)-Isomer,Norepinephrine, (+)-Isomer,Norepinephrine, (+,-)-Isomer
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D011460	Prostaglandins F	(9 alpha,11 alpha,13E,15S)-9,11,15-Trihydroxyprost-13-en-1-oic acid (PGF(1 alpha)); (5Z,9 alpha,11,alpha,13E,15S)-9,11,15-trihydroxyprosta-5,13-dien-1-oic acid (PGF(2 alpha)); (5Z,9 alpha,11 alpha,13E,15S,17Z)-9,11,15-trihydroxyprosta-5,13,17-trien-1-oic acid (PGF(3 alpha)). A family of prostaglandins that includes three of the six naturally occurring prostaglandins. All naturally occurring PGF have an alpha configuration at the 9-carbon position. They stimulate uterine and bronchial smooth muscle and are often used as oxytocics.	PGF
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D002463	Cell Membrane Permeability	A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.	Permeability, Cell Membrane