phospholamban Activators
Phospholamban (PLB) is a crucial regulatory protein primarily found in cardiac muscle cells, where it plays a pivotal role in modulating calcium uptake and release within the sarcoplasmic reticulum (SR). Its main function is to inhibit the activity of the sarcoplasmic reticulum calcium ATPase (SERCA), which is responsible for pumping calcium ions from the cytoplasm into the SR, leading to muscle relaxation. When PLB is phosphorylated, typically by protein kinase A (PKA) or calcium-calmodulin-dependent protein kinase (CaMKII), its inhibitory effect on SERCA is relieved, allowing for enhanced calcium reuptake into the SR. This phosphorylation-mediated activation of PLB results in increased contractility and relaxation of cardiac muscle fibers, contributing to the regulation of cardiac function and overall hemodynamics.
The activation of phospholamban is primarily achieved through phosphorylation events mediated by various protein kinases, such as PKA and CaMKII, in response to intracellular signaling cascades triggered by hormonal or neuronal stimulation. Upon activation of β-adrenergic receptors or increases in intracellular calcium levels, these kinases are activated, leading to the phosphorylation of PLB at specific serine residues. Phosphorylated PLB exhibits reduced affinity for SERCA, allowing for increased calcium transport into the SR and subsequent enhancement of myocardial contractility. Additionally, other regulatory mechanisms, such as alterations in PLB expression levels or interaction with regulatory proteins, may also contribute to its activation. Overall, the activation of phospholamban serves as a critical mechanism for regulating cardiac contractility and relaxation, thereby maintaining proper cardiac function and ensuring efficient blood circulation throughout the body.
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| Product Name | CAS # | Catalog # | QUANTITY | Price | Citations | RATING |
|---|---|---|---|---|---|---|
Forskolin | 66575-29-9 | sc-3562 sc-3562A sc-3562B sc-3562C sc-3562D | 5 mg 50 mg 1 g 2 g 5 g | $78.00 $153.00 $740.00 $1413.00 $2091.00 | 73 | |
Forskolin is a diterpene derivative that activates adenylate cyclase, leading to increased cAMP levels. Elevated cAMP levels can activate protein kinase A (PKA), which, in turn, phosphorylates phospholamban. Phosphorylated phospholamban relieves its inhibitory effect on the sarcoplasmic reticulum calcium pump (SERCA), promoting calcium reuptake into the sarcoplasmic reticulum and enhancing cardiac muscle contractility. | ||||||
Isoproterenol Hydrochloride | 51-30-9 | sc-202188 sc-202188A | 100 mg 500 mg | $28.00 $38.00 | 5 | |
Isoproterenol is a beta-adrenergic receptor agonist that stimulates adenylate cyclase, increasing cAMP production. The subsequent activation of PKA results in the phosphorylation of phospholamban, relieving its inhibition on SERCA. This process enhances calcium reuptake into the sarcoplasmic reticulum, positively affecting cardiac muscle contraction. | ||||||
Milrinone | 78415-72-2 | sc-201193 sc-201193A | 10 mg 50 mg | $165.00 $697.00 | 7 | |
Milrinone is a phosphodiesterase III inhibitor, increasing cAMP levels by preventing its degradation. Elevated cAMP activates PKA, leading to the phosphorylation of phospholamban. Phosphorylated phospholamban alleviates its inhibitory effect on SERCA, promoting calcium reuptake into the sarcoplasmic reticulum and enhancing cardiac muscle contractility. | ||||||
(RS)-Atenolol | 29122-68-7 | sc-204895 sc-204895A | 1 g 10 g | $79.00 $416.00 | 1 | |
Atenolol is a selective beta-1 adrenergic receptor antagonist that indirectly affects phospholamban activation. By blocking beta-1 adrenergic receptors, it inhibits the stimulatory effects of catecholamines, reducing cAMP levels and PKA activation. This results in decreased phosphorylation of phospholamban, maintaining its inhibitory influence on SERCA and modulating calcium handling in cardiac muscle. | ||||||
(±)-Bay K 8644 | 71145-03-4 | sc-203324 sc-203324A sc-203324B | 1 mg 5 mg 50 mg | $84.00 $196.00 $817.00 | ||
BAY K 8644 is an L-type calcium channel activator that increases calcium influx into cardiac cells. Elevated intracellular calcium levels can activate calmodulin-dependent protein kinase II (CaMKII), which can phosphorylate phospholamban. Phosphorylated phospholamban alleviates its inhibitory effect on SERCA, promoting enhanced calcium reuptake into the sarcoplasmic reticulum and positively impacting cardiac muscle contractility. | ||||||
Calyculin A | 101932-71-2 | sc-24000 sc-24000A | 10 µg 100 µg | $163.00 $800.00 | 59 | |
Calyculin A is a protein phosphatase inhibitor, preventing the dephosphorylation of phospholamban. By inhibiting protein phosphatases, particularly protein phosphatase 1 (PP1), calyculin A maintains the phosphorylated state of phospholamban. This sustained phosphorylation relieves its inhibitory effect on SERCA, facilitating increased calcium reuptake into the sarcoplasmic reticulum and enhancing cardiac muscle contractility. | ||||||
CGP 37157 | 75450-34-9 | sc-202097 sc-202097A | 5 mg 25 mg | $115.00 $463.00 | 3 | |
CGP-37157 is a mitochondrial Na+/Ca2+ exchange inhibitor that indirectly influences phospholamban activation. By inhibiting mitochondrial calcium efflux, it elevates intracellular calcium levels, potentially activating calmodulin-dependent protein kinase II (CaMKII). Activated CaMKII can phosphorylate phospholamban, relieving its inhibitory effect on SERCA and enhancing calcium reuptake into the sarcoplasmic reticulum, positively affecting cardiac muscle contractility. | ||||||
Okadaic Acid | 78111-17-8 | sc-3513 sc-3513A sc-3513B | 25 µg 100 µg 1 mg | $291.00 $530.00 $1800.00 | 78 | |
Okadaic Acid is a protein phosphatase inhibitor that prevents the dephosphorylation of phospholamban. By inhibiting protein phosphatases, particularly protein phosphatase 1 (PP1), okadaic acid maintains the phosphorylated state of phospholamban. This sustained phosphorylation relieves its inhibitory effect on SERCA, facilitating increased calcium reuptake into the sarcoplasmic reticulum and enhancing cardiac muscle contractility. | ||||||
KN-93 | 139298-40-1 | sc-202199 | 1 mg | $182.00 | 25 | |
KN-93 is a specific inhibitor of calmodulin-dependent protein kinase II (CaMKII). By inhibiting CaMKII, KN-93 prevents the phosphorylation of phospholamban. This sustained inhibition maintains phospholamban in its dephosphorylated state, strengthening its inhibitory effect on SERCA. Consequently, reduced calcium reuptake into the sarcoplasmic reticulum occurs, influencing cardiac muscle contractility. | ||||||
SL-327 | 305350-87-2 | sc-200685 sc-200685A | 1 mg 10 mg | $107.00 $332.00 | 7 | |
SL-327 is a specific inhibitor of mitogen-activated protein kinase kinase (MEK), a component of the extracellular signal-regulated kinase (ERK) signaling pathway. The ERK pathway can phosphorylate phospholamban, modulating its inhibitory effect on SERCA. By inhibiting MEK, SL-327 disrupts this phosphorylation, potentially maintaining phospholamban in its dephosphorylated state. This sustained inhibition impacts calcium handling in cardiac muscle, affecting contractility. | ||||||