muscle contraction

Phorbol 12,13-dibutyrate (Phorbol dibutyrate) is a PKC activator that inhibits α1-adrenoceptor-mediated positive inotropic effects in a concentration-dependent manner, induced by contraction of isolated rabbit vascular smooth muscle.

Prostaglandin E2 (PGE2) is a natural hormone-like substance involved in various physiological functions, including the contraction and relaxation of smooth muscles, dilation and constriction of blood vessels, regulation of blood pressure, and modulation of inflammation. It can be used to induce neuropathic pain models.

Regrelor disodium (INS 50589) is a P2Y12 receptor antagonist that prevents thrombosis, effectively inhibits vascular smooth muscle cell contraction, curbs cell proliferation, and reduces inflammation.

Dantrolene sodium (Dantrolene sodium salt) is a skeletal muscle relaxant and can interfere with excitation-contraction coupling in the muscle fiber. It is used for the treatment of spasticity and other neuromuscular abnormalities. Its mechanism of action is may not central, but dantrolene is usually grouped with the central muscle relaxants.

Carbachol (Carbamoylcholine chloride), an analog of acetylcholine, serves as a valuable tool in the investigation of various physiological responses mediated by nicotinic (nAChR) and muscarinic (mAChR) acetylcholine receptors. These responses include smooth muscle contraction, gut motility, and neuronal signaling. Known for its agonistic properties, Carbachol activates both nAChR and mAChR, with reported Ki values ranging from 10 to 10,000 nM for different receptor types and experimental preparations.

Doxylamine Succinate is a pyridine derivate histamine H1 antagonist with pronounced sedative properties. Doxylamine succinate (Decapryn) competitively blocks the histamine H1 receptor and limits the typical allergic and anaphylactic responses, including bronchoconstriction, vasodilation, increased capillary permeability, and spasmodic contraction of the gastrointestinal smooth muscle, caused by actions of histamine on bronchial and gastrointestinal smooth muscles, and on capillaries. This drug also prevents histamine-induced pain and itching of the skin and mucous membranes.

Salbutamol (Albuterol) stimulates beta2-adrenergic receptors in the lungs, thereby activating the enzyme adenylate cyclase that catalyzes the conversion of ATP to cyclic-3', 5'-adenosine monophosphate (cAMP). Salbutamol Sulfate is the sulfate salt of the short-acting sympathomimetic agent albuterol, a 1:1 racemic mixture of (R)-albuterol and (S)-albuterol with bronchodilator activity. Increased cAMP concentrations relax the bronchial smooth muscle, relieve bronchospasms, and reduce inflammatory cell mediator release, especially from mast cells. To a lesser extent, Salbutamol stimulates beta1-adrenergic receptors, thereby increasing the force and rate of myocardial contraction.

Nicardipine hydrochloride (YC-93 Hydrochloride) is the hydrochloride salt form of nicardipine, a synthetic derivative of nitrophenyl-pyridine and potent calcium channel blocker, Nicardipine (Nifedipine Family) blocks calcium ions from certain cell walls and inhibits contraction of coronary and peripheral arteries, resulting in lowered oxygen requirements for heart muscle and decreased arterial contraction and spasm. It is used clinically as a cerebral and coronary vasodilator.

Hydralazine hydrochloride (Apresoline) is the hydrochloride salt of hydralazine, a phthalazine derivative with antihypertensive and potential antineoplastic activities. Hydralazine alters intracellular calcium release and interferes with smooth muscle cell calcium influx, resulting in arterial vasodilatation. This agent also inhibits the phosphorylation of myosin protein and chelation of trace metals required for smooth muscle contraction, resulting in an increase in heart rate, stroke volume, and cardiac output. In addition to its cardiovascular effects, hydralazine inhibits DNA methyltransferase, which may result in inhibition of DNA methylation in tumor cells.

Dantrolene depresses excitation-contraction coupling in skeletal muscle by binding to the ryanodine receptor 1 and decreasing intracellular calcium concentration. Ryanodine receptors mediate the release of calcium from the sarcoplasmic reticulum, an essential step in muscle contraction. Dantrolene sodium hemiheptahydrate (Sodium dantrolene) is the sodium salt form of dantrolene, a hydantoin derivative, and direct-acting skeletal muscle relaxant.

PD-102807 is a selective and competitive M4 muscarinic receptor antagonist (IC50 = 90.7 nM), with IC50 values of 950–7412 nM for M1, M2, M3, and M5 receptors, and can be used for Parkinson's disease research, as well as to inhibit airway smooth muscle (ASM) contraction.

Oxytocin (Syntocinon) is a mammalian neuropituitary hormone, a pleiotropic hypothalamic peptide and ligand for the oxytocin receptor, which contributes to labor, lactation, and pro-social behavior. Oxytocin has the ability to stimulate mammary secretion of breast milk, promote contraction of uterine smooth muscle during labor, and facilitate mothering.

NP-1815-PX is a selective P2X4 receptor antagonist with anti-inflammatory and analgesic properties. It inhibits guinea pig tracheal/bronchial smooth muscle contraction and can be used to study chronic pain.

L-Hyoscyamine (Daturine) functions as a non-selective, competitive antagonist of muscarinic receptors, thereby inhibiting the parasympathetic activities of acetylcholine on the salivary, bronchial, and sweat glands, as well as the eye, heart, bladder, and gastrointestinal tract. Hyoscyamine is a belladonna alkaloid derivative and the levorotatory form of racemic atropine isolated from the plants Hyoscyamus niger or Atropa belladonna, which exhibits anticholinergic activity. These inhibitory effects cause a decrease in saliva, bronchial mucus, gastric juices, and sweat. Furthermore, its inhibitory action on smooth muscle prevents bladder contraction and decreases gastrointestinal motility.

Cyclobuxine D, a steroidal alkaloid extracted from Buxus microphylla, exhibits significant bradycardia effects on rat hearts and inhibits acetylcholine and Ba++-induced longitudinal muscle contractions in isolated rabbit jejunum.

Lysipressin ([Lys8]-Vasopressin), Induces contraction of the rabbit urinary bladder smooth muscle, activate adenylate-cyclase. Lysipressin is Antidiuretic hormone that have been found in pigs and some marsupial families.

Lysipressin acetate(50-57-7(fb_acetate)) ([Lys8]-Vasopressin acetate) , Induces contraction of the rabbit urinary bladder smooth muscle, activate adenylate-cyclase. Lysipressin is Antidiuretic hormone that have been found in pigs and some marsupial families.

Rivanicline hemioxalate, also known as RJR-2403 hemioxalate or (E)-Metanicotine hemioxalate, is a chemical compound acting as a neuronal nicotinic receptor agonist with pronounced selectivity for the α4β2 receptor subtype, showing over 1,000-fold greater selectivity for this subtype (Ki=26 nM) compared to α7 receptors (Ki=3.6 μM). Its in vitro studies demonstrate no significant activation of nAChRs in PC12 cells, muscle type nAChRs, or muscarinic receptors at concentrations up to 1 mM. Furthermore, Rivanicline displayed less than one-tenth the potency of nicotine in inducing ileum contraction, with substantially lower efficacy, and failed to antagonize nicotine-induced stimulation of muscle or ganglionic nAChR functions, with an IC50 value greater than 1 mM. Chronic exposure to Rivanicline at 10 microM led to up-regulation of high-affinity nAChRs in M10 cells, mimicking effects observed with nicotine. In vivo studies revealed that Rivanicline significantly reversed scopolamine-induced amnesia and improved working and reference memory in a rat model, while being 15 to 30 times less potent than nicotine in affecting body temperature, respiration, and other physiological responses. Metanicitone's potency was approximately five times lower than nicotine in tail-flick tests following subcutaneous administration, yet slightly more potent upon central administration.

Midodrine is converted to its active metabolite, desglymidodrine by deglycination reaction. Desglymidodrine selectively binds to and activates alpha-1-adrenergic receptors of the arteriolar and venous vasculature. This causes smooth muscle contraction and leads to an elevation of blood pressure. Desglymidodrine diffuses poorly across the blood-brain barrier and is therefore not associated with effects on the central nervous system. Midodrine hydrochloride (Pro-Amatine) is the hydrochloride salt form of midodrine, a direct-acting prodrug and sympathomimetic agent with antihypotensive properties.

U-46619 is an effective thromboxane A2 (TXA2) agonist and a thromboxane A2 analog (endoperoxide), capable of inducing contraction in the aortic smooth muscle (SM) of mice with a myosin light chain 9 (Myl9) gene deletion.

Ro 25-1553 is a 31-amino acid analog of vasoactive intestinal peptide (VIP) that functions as an agonist for the VIP2 receptor (VPAC2 receptor). In guinea pig models, Ro 25-1553 exhibits bronchodilator effects on tracheal smooth muscle contraction induced by neural stimuli or Carbachol.

Acetylethylcholine mustard hydrochloride is a choline acetyl-transferase inhibitor that decreases muscle contraction frequency by inhibiting the synthesis of acetyl-beta-methylcholine (Ach), with a half-maximal inhibitory concentration (IC50) of 1.22 mM. It serves as an irreversible ligand for the high-affinity choline transport system and functions as a specific presynaptic long-acting cholinergic toxin. Additionally, acetylethylcholine mustard hydrochloride is a precursor to the ethylcholine mustard aziridinium ion.

BKCa activator-1 (Compound 51b) is an orally active activator of BKCa calcium-activated potassium channels with an EC50 of 2.82 μM. It promotes K+ efflux, leading to cell membrane hyperpolarization and inhibition of smooth muscle contraction. In a spontaneous hypertensive rat (SHR) model, it alleviates urinary incontinence and exhibits antitussive effects in a guinea pig cough model.

Litorin, an amphibian bombesin peptide derivative, suppresses nutriment, stimulates smooth muscle contraction, and enhances the secretion of gastrin, gastric acid, and pancreatic secretions.