Biomaterial Database

Modulation on neuromuscular transmission by endogenous and exogenous prostaglandins in the guinea-pig mesenteric artery. 1982

H Kuriyama, and Y Makita

1. At concentrations of 2.8 x 10(-8)-2.8 x 10(-6) M, prostaglandins (PGs; PGE(1), PGE(2) and PGF(2alpha)) had no effect on membrane potential and resistance of smooth muscles of the guinea-pig mesenteric artery. PGs (2.8 x 10(-8) M) suppressed the contraction evoked by perivascular nerve stimulation, but did not suppress the contraction evoked by direct muscle stimulation.2. PGs (2.8 x 10(-8) M) suppressed the e.j.p.s evoked by repetitive perivascular nerve stimulation but preserved the facilitation process of e.j.p.s evoked by any given stimulus frequency (0.1-1.0 Hz).3. The relationships between e.j.p. amplitudes and [Ca](o) plotted on log scales in the presence or absence of PGE(2) were not parallel. High concentrations of [Ca](o) prevented the inhibitory actions of PGs on the amplitude of e.j.p.s.4. PGE(2) did not suppress the activity of nerve fibres contributing to the generation of e.j.p.5. Indomethacin (10(-6) M) enhanced the amplitude of e.j.p.s and the frequency of miniature e.j.p.s with no change in the membrane potential and resistance of smooth muscles; these actions of indomethacin were suppressed by PGE(2) (2.8 x 10(-8) M).6. Phentolamine (10(-7) M) enlarged and yohimbine (10(-7) M) reduced the amplitude of the first e.j.p. evoked by a train stimulation, but the maximum amplitude of e.j.p., after the facilitation was completed, was in both cases much larger than that observed in the control. The enhancement of the transmission process was also suppressed by PGs (2.8 x 10(-8) M).7. The results indicate that in the guinea-pig mesenteric artery, PGs mainly suppress chemical transmitter release from nerve terminals due to interactions with Ca influx, but not due to interaction with presynaptic alpha-adrenoceptors. Endogenous PG may act as a regulator substance in neuromuscular transmission.

UI	MeSH Term	Description	Entries
D007213	Indomethacin	A non-steroidal anti-inflammatory agent (NSAID) that inhibits CYCLOOXYGENASE, which is necessary for the formation of PROSTAGLANDINS and other AUTACOIDS. It also inhibits the motility of POLYMORPHONUCLEAR LEUKOCYTES.	Amuno,Indocid,Indocin,Indomet 140,Indometacin,Indomethacin Hydrochloride,Metindol,Osmosin
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D008638	Mesenteric Arteries	Arteries which arise from the abdominal aorta and distribute to most of the intestines.	Arteries, Mesenteric,Artery, Mesenteric,Mesenteric Artery
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
D009435	Synaptic Transmission	The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.	Neural Transmission,Neurotransmission,Transmission, Neural,Transmission, Synaptic
D009469	Neuromuscular Junction	The synapse between a neuron and a muscle.	Myoneural Junction,Nerve-Muscle Preparation,Junction, Myoneural,Junction, Neuromuscular,Junctions, Myoneural,Junctions, Neuromuscular,Myoneural Junctions,Nerve Muscle Preparation,Nerve-Muscle Preparations,Neuromuscular Junctions,Preparation, Nerve-Muscle,Preparations, Nerve-Muscle
D011453	Prostaglandins	A group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase pathway. They are extremely potent mediators of a diverse group of physiological processes.	Prostaglandin,Prostanoid,Prostanoids
D011458	Prostaglandins E	(11 alpha,13E,15S)-11,15-Dihydroxy-9-oxoprost-13-en-1-oic acid (PGE(1)); (5Z,11 alpha,13E,15S)-11,15-dihydroxy-9-oxoprosta-5,13-dien-1-oic acid (PGE(2)); and (5Z,11 alpha,13E,15S,17Z)-11,15-dihydroxy-9-oxoprosta-5,13,17-trien-1-oic acid (PGE(3)). Three of the six naturally occurring prostaglandins. They are considered primary in that no one is derived from another in living organisms. Originally isolated from sheep seminal fluid and vesicles, they are found in many organs and tissues and play a major role in mediating various physiological activities.	PGE
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
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea