| M2muscarinic acetylcholine receptor (mAChR2)receptor andβ2-adrenergic receptor (β2-AR) belong to the G protein-coupled receptor subtypes, and they can also be G protein-binding G protein-coupled receptor kinase 2 (GRK2) phosphorylation of regulation. GRK2 previously also known as theβ-adrenergic receptor kinase (βARK). GRK2 phosphorylation of the substrate including mAChR2 2 - ARβandβ2-AR, the G protein-binding receptors. MAChR2 and phosphorylation-dependent activation of respectively as carbamoyl choline (carbachol), or special than he forests (turbutaline) in the role. Muscarinic acetylcholine receptor m2 andβ2-adrenergic receptor involved in the phosphorylation of a desensitization process, especially those dependent on the agonist G protein binding receptor phosphorylationof aspecific agonist-mediated process of desensitization In the closure of receptor-mediated signal transduction pathway, desensitization to play a vital role. Long-term use of a clinical treatment agonist drugs, organizations or cells to decrease the sensitivity of agonist drugs, theagonist-specificdesensitization(agonist-specific desensitization) mechanism has not yet very clear, and may be subject to speculation Phosphorylation of the body. These receptors involved in the phosphorylation of a desensitization process, especially those dependent on the agonist combination m2 G protein receptor phosphorylation is considered to be a specific agonist-mediated desensitization process. When stimulants and receptor binding, the receptor involved triggered the cascade of phosphorylation. For the activation of receptor stimulants, the impact of protein kinase catalytic receptor phosphorylation. MAChR2 receptor in the regulation of doping andβ2-AR desensitization, and the reduction of the role is very important. Embedded in the membrane of the third ring of amino acid residues (serine and threonine) phosphorylation of its dependence on the occurrence of mediated activation of the role of desensitization. Our previous results show that some organic pesticides will be combined in different ways and modified m2 receptor, the receptor leading to the selective regulation of the different roles, thereby creating m2 receptor function of different changes. Well m2 receptor andβ2-AR is how to stimulants activation, and m2 affect the phosphorylation of the receptor? Is it because of stimulants increased synergies receptor desensitization effect? Experimental study on the use of isotope-labeled [32 P] ATP radioactive autoradiography and liquid scintillation 2 - AR for the study,βcounting methods, to the purified rat brain mAChR2 and observation carbamoyl choline, liver and atropine - m2 respectively on the receptor and terbutaline andβ2-AR heparin membrane protein phosphorylation process, and to explore the activators or inhibitors of G protein-coupled receptor kinase 2 (GRK2)-mediated biliary Alkali can m2 andβ2-AR receptor phosphorylation of regulatory mechanisms. Discussion on how to make the 2 - AR receptor activation of receptorβstimulant m2 receptor and phosphorylation trigger a cascade reaction of these receptors involved in the adjustment process in some specific processes such as receptor desensitization and internalization and reduced the initial mechanism.Methods and results :1. Affinity column chromatography showed that the SDS polyacrylamide gel electrophoresis analysis of the purified rat brain mAChR2 see results m2 receptor is a relative molecular weight of about 68 kd protein.2. Electrophoresis and autoradiography method of radioactive liquid scintillation techniques and test results show that carbamoyl significantly enhance m2 cholinergic receptor phosphorylation, and atropine or heparin (GRK2 inhibitor) completely blocked the receptor m2 The phosphorylation.3. Electrophoresis and autoradiography method of detecting radioactive carbamoyl m2 enhance cholinergic receptor phosphorylation of the dose relationship.4. Electrophoresis and autoradiography method of radioactive liquid scintillation techniques and test results can be enhanced terbutaline adrenergic receptor phosphorylation, and heparin m2 completely blocked the phosphorylation of the receptor.5. Carbamoyl choline not affect adrenergic receptor phosphorylation, terbutaline also not be affected m2 receptor phosphorylation. Effects of the carbamoyl phosphate, as well as mAChR2 terbutaline adrenergic receptor phosphorylation is selective enhancement of the role of the results.6. The experimental results show that cell, carbamoyl HEL299 cholinergic cells can be enhanced phosphorylation of the receptor m2, atropine HEL299 cells can inhibit the phosphorylation of the receptor m2, but significant role than in vitro, suggesting that the phosphorylation of the receptor m2 in the in vivo and may be affected by the activator inhibitor common functional regulation.The experimental results show that m2 andβ2-AR receptor phosphorylation-dependent activation of the role of the agent, but confirmed that the activator mAChR2 andβ2-AR phosphorylation of a selective enhancement of the role, together with an explanation directly with atropine m2 receptor binding, it is possible to directly integrate the GRK2 very sensitive m2 receptors in the intracellular serine third ring and threonine residues; revealed carbamoyl choline, and special atropine He Lin, and some other cloth m2 receptor andβ2-AR activation agent and inhibitor both in vitro cell level or the M2 receptor andβ2-AR phosphorylation of an important regulatory role. Tip activator carbamoyl choline and terbutaline enhance m2 andβ2-AR receptor phosphorylation of the receptor may be m2 andβ2-AR activation of an important part, which began to accelerate down receptor sensitivity, receptor Tolerance of enhanced m2 andβ2-AR receptor phosphorylation may postsynaptic receptor sensitivity is reduced tolerance of growth receptor caused the main mechanism.
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