The inhibitory effect of X537A on vascular and intestinal smooth muscle contraction. 1984

K Murakami, and H Karaki, and H Nakagawa, and N Urakawa

The effects of X537A (Lasalocid) on contractions induced in vascular and intestinal smooth muscles were examined. High K-induced sustained contractions were inhibited by X537A with an IC50 of 2.8 X 10(-6) M in rabbit aorta and 8.8 X 10(-8) M in guinea-pig Taenia coli. Changing the Ca concentration in the medium did not modify the effect of X537A. X537A also inhibited the noradrenaline-induced contraction in aorta (IC50 = 7.0 X 10(-8) M). In a solution without added glucose, the inhibitory effect of X537A on the K-induced contraction in aorta was augmented (IC50 = 1.5 X 10(-8) M). Under hypoxic conditions, the inhibitory effects of X537A on the noradrenaline-induced contractions in aorta and on the K-induced contraction in T. coli were decreased (IC50 greater than 10(-5) M and 3.2 X 10(-6) M, respectively). X537A inhibited the K-induced increase in cellular 45Ca content in aorta measured by a modified lanthanum method. However, the IC50 for 45Ca uptake (6.6 X 10(-7) M) was lower than that for K-induced contraction. In both tissues, X537A decreased the ATP content. Oxygen consumption of rat liver mitochondria was inhibited by X537A. From these results, it is concluded that the inhibitory effect of X537A on the noradrenaline-induced contraction in aorta and the K-induced contraction in T. coli, but not the K-induced contractions in aorta, may be due to the inhibition of aerobic metabolism.

UI MeSH Term Description Entries
D007422 Intestines The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE. Intestine
D007832 Lasalocid Cationic ionophore antibiotic obtained from Streptomyces lasaliensis that, among other effects, dissociates the calcium fluxes in muscle fibers. It is used as a coccidiostat, especially in poultry. Avatec,Lasalocid A,Ro 2-2985,X-537A,Ro 2 2985,Ro 22985,X 537A,X537A
D008297 Male Males
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
D009130 Muscle, Smooth Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed) Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
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
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
D010101 Oxygen Consumption The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346) Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D011817 Rabbits A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes. Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
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

Related Publications

K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
March 1994, The American journal of physiology,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
November 1978, European journal of pharmacology,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
March 1986, Pharmacological research communications,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
June 1970, The Journal of pharmacology and experimental therapeutics,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
December 1991, Japanese journal of pharmacology,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
April 2022, Current medical science,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
December 2002, British journal of pharmacology,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
September 1968, Life sciences,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
January 1964, Canadian Medical Association journal,
K Murakami, and H Karaki, and H Nakagawa, and N Urakawa
July 1988, British journal of pharmacology,
Copied contents to your clipboard!