Mebeverine hydrochloride (Colofac Hydrochloride), a β-phenylethylamine derivative, is a potent α1 repector inhibitor, relaxing the muscles in and around the gut.

Octadecanal (stearaldehyde) is present in the thigh and chest muscles.

Phe-Met-Arg-Phe Like Peptide acetate (Pqdpflrfamide acetate) is a FMRF-like peptide from visceral and somatic muscles of the snail Helix aspersa. FMRF (Phe-Met-Arg-Phe) is a neuropeptide peptide consisting of 4 amino acid residues.

Endomorphins-2 (EM-2) could decrease both the frequency and amplitude of the sEPSC of the motoneurons in lamina IX, which was reversed by the MOR antagonist CTOP. EM-2-IR fibers originated from primary afferent fibers form symmetric synaptic connections with motoneurons innervating skeletal muscles of the lower limbs in lamina IX of the spinal ventral horn and EM-2 might exert inhibitory effects on the activities of these motoneurons through both presynaptic and postsynaptic mechanisms.

Sodium creatine phosphate dibasic tetrahydrate (Creatine phosphate disodium salt tetrahydrate) mainly exists in the skeletal muscles of vertebrates. It is a substrate for the determination of creatine kinase and can be used for the regeneration of ATP during skeletal muscle contraction.

Diphylline (Diprophylline) is a xanthine derivative. Diphylline exerts bronchodilator effects and to a lesser extent vasodilator and diuretic properties. Diphylline probably acts as a competitive inhibitor of phosphodiesterase which leads to an increase in intracellular cAMP. This results in relaxation of bronchial smooth muscle and other smooth muscles. Diphylline may also antagonize adenosinereceptors. Diphylline is used in the treatment of acute bronchial asthma, chronic bronchitis and emphysema.

Prazosin hydrochloride (Vasoflex) reduces peripheral resistance and relaxes vascular smooth muscles as a selective adrenergic alpha-1 antagonist by a mechanism not completely known. Prazosin hydrochloride is a synthetic piperazine derivative with hypotensive antiadrenergic properties, It is used in the treatment of heart failure, hypertension, pheochromocytoma, Raynaud's syndrome, prostatic hypertrophy, and urinary retention.

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.

Fipronil (Fluocyanobenpyrazole) is a broad-use insecticide that belongs to the phenylpyrazole chemical family. Fipronil is a broad-spectrum insecticide that disrupts the insect central nervous system by blocking GABA-gated chloride channels and glutamate-gated chloride (GluCl) channels, resulting in central nervous system toxicity. This causes hyperexcitation of contaminated insects' nerves and muscles. Specificity of fipronil on insects may come from a better efficacy on GABA receptor, but also because GluCl channels do not exist in mammals.

Uperolein, a physalaemin-like endecapeptide derived from the skin of Uperoleia rugosa and Uperoleia marmorata, exhibits spasmodic activity on the gastrointestinal tract and longitudinal muscles [1] [2] [3].

GW-Amide is a molluscan neuropeptide that exhibits potent modulatory effects on molluscan muscles.

D-Epinephrine can be used as a hormone, neurotransmitter, and medication. Epinephrine can be normally obtained from the adrenal glands and certain neurons. It involves in the fight-or-flight response by increasing blood flow to muscles, output of the hear

Homoanserine Nitrate is a dipeptide found in mammalian brains and muscles.

Phospho-L-arginine is a phosphorylated form of L-arginine and a highly diffusible, high-energy metabolite and phosphagen involved in energy storage in invertebrates including crustaceans, insects, and Trypanosoma species. In the locust L. migratoria, phospho-L-arginine is found in the flight muscles, where it acts as both a buffer system and shuttle mechanism for high-energy phosphate. Measurement of phospho-L-arginine by 31P-NMR spectroscopy has been used to study invertebrate energy metabolism in vivo.

Phosphocreatine dipotassium, primarily found in the skeletal muscles of vertebrates and one of organic compounds known as alpha amino acids and derivatives.

TriacetonaMine (Vincubine) protects the activitis of superoxide dismutase(SOD) and creatine phos-phate kinase (CPK); it also inhibits CaCl2 induced agglomeration of thromocyte. Triacetonamine can improve the constructile function of heart mus-cles of acute anemia and decrease the content of malodialdehyde (MDA) in the heart muscles.

Eperisone is a centrally acting muscle relaxant and antispastic agent utilized in the treatment of conditions distinguished by muscle stiffness and pain. Its mechanism of action involves the relaxation of skeletal muscles and vascular smooth muscles, resulting in a range of beneficial effects including reduction of myotonia, enhancement of circulation, and suppression of the pain reflex. Additionally, Eperisone exhibits inhibitory properties on the pain reflex pathway and exerts a vasodilator effect.

Metaxalone (Methaxalonum) (marketed by King Pharmaceuticals under the brand name Skelaxin ) is a muscle relaxant used to relax muscles and relieve pain caused by strains, sprains, and other musculoskeletal conditions.

Choline bitartrate (2-hydroxyethyl(trimethyl)azanium) is a form of the nutrient choline which is found in foods. Choline is necessary for normal liver and kidney function and a component of the neurotransmitter acetylcholine, a chemical that facilitates communication between the nerves and muscles.

BDF 9148, a Na(+)-channel modulator, increases the contractile force of guinea-pig atria and papillary muscles.

Vindorosine has blood vessel relaxation effect, possible underlying mechanisms involving the inhibition of Ca(2+) entry via L-type Ca(2+) channels in vascular smooth muscles.

7-O-Methyleriodictyol is a flavanone isolated from Artemisia monosperma and shows biological effects on rat isolated smooth muscles.

Visnagin has acute hypotensive, anti-inflammatory, and neuroprotective effects, it protects against doxorubicin-induced cardiomyopathy through modulation of mitochondrial malate dehydrogenase.

Propiverine is a potent antimuscarinic agent that effectively inhibits cellular calcium influx, leading to the reduction of muscle spasm. It exhibits neurotropic and musculotropic effects specifically on the smooth muscles of the urinary bladder. Propiverine proves valuable in research concerning overactive bladder (OAB) [1] [2].

Benzthiazide (Lemazide) is used in the therapy of edema and hypertension. Like other thiazides, benzthiazide accelerates water loss from the body (diuretics). They inhibit Na+/Cl- reabsorption from the distal convoluted tubules in the kidneys. Thiazides also cause loss of potassium and an increase in serum uric acid. Thiazides are often used to treat hypertension, but their hypotensive effects are not necessarily due to their diuretic activity. Thiazides have been shown to prevent hypertension-related morbidity and mortality although the mechanism is not fully understood. Thiazides cause vasodilation by activating calcium-activated potassium channels (large conductance) in vascular smooth muscles and inhibiting various carbonic anhydrases in vascular tissue.

GS 283 is a Ca(2+) antagonist. GS 283 is also a weak histamine and muscarinic receptor blocker in rat and guinea pig tracheal smooth muscles.

Adenosine 3’-monophosphate is a nucleotide and metabolite formedviahydrolysis of 2’,3’-cAMP by metal-dependent phosphodiesterases.1It reduces proliferation of rat preglomerular vascular smooth muscles cells (PGVSMCs) and glomerular mesangial cells (GMCs) in a concentration-dependent manner, an effect that is abolished by the adenosine A2Breceptor antagonist MRS1754.2Adenosine 3’-monophosphate is also a metabolic intermediate in the biosynthesis of adenosine .

Clofeverine hydrochloride is the salt form of Clofeverine (free base), a highly selective relaxant for gastrointestinal smooth muscles with a beta-receptor stimulative nature. On isolated ileum, the inhibitory effect of clofeverine for spontaneous motility was comparable to that of isoproterenol and 100 times higher than that of papaverine.

GYKI-16638 is a novel antiarrhythmic agent that demonstrates combined class IB and class III antiarrhythmic properties in human ventricular muscles, similar to the electrophysiological findings after chronic amiodarone treatment. In addition, GYKI 16638 h

Tamsulosin ((R)-(-)-YM12617 free base) is an alpha1A adrenergic receptor antagonist for the symptomatic treatment of benign prostatic hyperplasia (BPH). Tamsulosin is used to treat difficulty urinating, a common symptom of an enlarged prostate. Tansulosin and other drugs called alpha blockers work by relaxing the neck muscles of the bladder and muscle fibers in the prostate itself, making it easier to urinate.

L-Proline (proline) is a nonessential amino acid in humans. It is an essential component of collagen and is important for proper functioning of joints and tendons. It also helps maintain and strengthen heart muscles.

Clofeverine (free base) is a highly selective relaxant for gastrointestinal smooth muscles with a beta-receptor stimulative nature. On isolated ileum, the inhibitory effect of clofeverine for spontaneous motility was comparable to that of isoproterenol and 100 times higher than that of papaverine.

1-1(Z)-Hexadecenyl-2-palmitoyl-sn-glycero-3-PC, a plasmalogen, appears in various rat tissues including the liver, heart, kidney, and both gluteus and soleus muscles, as well as visceral and subcutaneous adipose tissues. It serves in lipid bilayer synthesis to investigate how amphiphilic compounds, like lysophosphatidylcholine (1-palmitoyl-2-hydroxy-sn-glycero-3-PC) and lysoplasmenylcholine, influence membrane dynamics.

Quinidine hydrochloride monohydrate is an optical isomer of quinine, extracted from the bark of the Cinchona tree and similar plant species. It prolongs cellular action potential and decreases automaticity. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. Quinidine also blocks muscarinic and alpha-adrenergic neurotransmission.

Creatine (Methylguanidoacetic acid) is an amino acid that occurs in vertebrate tissues and in urine. In muscle tissue, creatine generally occurs as phosphocreatine. Creatine is excreted as creatinine in the urine. Creatine functions as part of the cell's energy shuttle. The high energy phosphate group of ATP is transferred to creatine to form phosphocreatine in the following reaction: Cr + ATP <-> PCr + ADP. This reaction is reversibly catalyzed by creatine kinase. In the human body, creatine is synthesized mainly in the liver by the use of parts from three different amino acids: arginine, glycine, and methionine. 95% of it is later stored in the skeletal muscles and the rest is stored in the brain, heart, and testes.

Saterinone is a potent and selective phosphodiesterase III inhibitor and a potent antagonist of the vascular α-1-adrenoceptor. Saterinone has vasodilatory properties and can be used in the acute treatment of chronic heart failure. Saterinone inhibited crude cAMP phosphodiesterase (PDE) activity in guinea pig right ventricular homogenates The ic50 value is 2.3 × 10(-5) mol/l.

Cinitapride (Blaston) is a gastroprokinetic agent. It slows the actions of the muscles to reduce the symptoms of conditions such as acid reflux, delayed gastric emptying, and ulcer dyspepsia. Cinitapride acts as an antagonist of the 5-HT2 receptors and as an agonist of the 5-HT1 and 5-HT4 receptors.

Eicosapentaenoic acid (EPA) is metabolized into epoxyeicosatetraenoic acids (EpETE) by multiple cytochrome P450 isoforms. The predominant compound of this epoxygenase pathway, (±)17(18)-EpETE, induces relaxation in vascular and airway smooth muscles through its action on large conductance Ca2+-activated K+ (BKCa) channels, specifically by binding to the BKα channel subunits. Another notable epoxygenase pathway derivative, (±)11(12)-EpETE, also generated from EPA via CYP450 activity in both in vitro and in vivo studies, has biological and physiological roles that are yet to be fully elucidated.

Epinephrine HCl, a compound functioning as a hormone, neurotransmitter, and medication, is synthesized by adrenal glands and some neurons. It is essential in the fight-or-flight response, enhancing blood flow to muscles, heart output, pupil dilation, and blood sugar levels through its interaction with alpha and beta receptors. Epinephrine HCl is present in various animals and some unicellular organisms.

Diprophylline-d6 is a deuterated compound of Diprophylline. Diprophylline has a CAS number of 479-18-5. Dyphylline is a xanthine derivative. Dyphilline exerts bronchodilator effects and to a lesser extent vasodilator and diuretic properties. Dyphilline probably acts as a competitive inhibitor of phosphodiesterase which leads to an increase in intracellular cAMP. This results in relaxation of bronchial smooth muscle and other smooth muscles. Dyphylline may also antagonize adenosinereceptors. Dyphylline is used in the treatment of acute bronchial asthma, chronic bronchitis and emphysema.

MT-134 is a SkMII -specific inhibitor and has excellent exposure in muscles.

Ambrein is a triterpene alcohol that is the chief constituent of ambergris, a secretion from the digestive system of the sperm whale, and has been suggested as the possible active component producing the supposed aphrodisiac effects of ambergris. It serves as the biological precursor for a number of aromatic derivatives such as ambroxan and is thought to possess fixative properties for other odorants. It has been shown to act as an analgesic and it has been proven to increase sexual behavior in rats, providing some support for its traditional aphrodisiac use. Ambrein has also been shown to decrease spontaneous contractions of smooth muscles in rats, guinea pigs, and rabbits. It is able to reduce these contractions by serving as an antagonist and interfering with the Ca2+ ions from outside of the cell.

Phe-Met-Arg-Phe-like peptide, derived from the visceral and somatic muscles of the snail Helix aspersa, is a neuropeptide known as FMRF (Phe-Met-Arg-Phe). This peptide comprises four amino acid residues[1].

Antazoline phosphate is an antihistamine with anticholinergic properties. Antazoline prevents the typical allergic symptoms on capillaries, mucous membranes, skin, and gastrointestinal and bronchial smooth muscles by antagonizing the histamine H1 receptor

Mephenoxalone is a muscle relaxant and mild anxiolytic. It inhibits neuron transmission and relaxing skeletal muscles by inhibiting the reflex arc.

Demoxytocin, an analog of oxytocin and a heterodetic cyclic peptide, enhances cell membrane permeability to elevate calcium ion levels in smooth muscle cells, thereby augmenting contraction, including the smooth muscles of the uterus. This compound mirrors oxytocin's function and is utilized in studies focusing on labor induction following premature rupture [1].

Acefylline piperazine is a stimulant drug of the xanthine chemical class. It acts as an adenosine receptor antagonist. Acephylline piperazine is a theophylline derivative with a direct bronchodilator action. It has the advantages over theophylline in being far less toxic and producing minimal gastric irritation. It is indicated for the treatment of asthma, emphysema, acute and chronic bronchitis associated with bronchospasm.Acefylline relaxes smooth muscles, relieves bronchospasm & has a stimulant effect on respiration. It stimulates the myocardium & central nervous system, decreases peripheral resistance & venous pressure & causes diuresis. The mechanism of action is still not clear, inhibition of phosphodiesterase with a resulting increase in intracellular cyclic AMP does occur, but not apparently at concentrations normally used for clinical effect. Other proposed mechanisms of action include adenosine receptor antagonism, prostaglandin antagonism & effects on intracellular......

Antho-Riamide I is an active peptide. It also inhibits the spontaneous contraction of sea anemone muscles.

Dacarbazine citrate is an alkylating agent used to treat cancers of the lymphatic system and malignant melanoma (a type of skin cancer) in patients with certain conditions: islet cell carcinoma (part of the pancreas) Soft tissue sarcoma (cancer of muscles