Qhov sib txawv tseem ceeb ntawm H1 thiab H2 receptors yog tias H1 receptor khub niam txiv nrog Gq / 11 stimulating phospholipase C thaum H2 receptor cuam tshuam nrog Gs kom qhib adenylyl cyclase.
Histamine yog ib qho organic nitrogenous compound uas suav nrog cov tshuaj tiv thaiv hauv zos. Tsis tas li ntawd, nws ua hauj lwm raws li ib tug neurotransmitter nyob rau hauv lub hauv nruab nrab lub paj hlwb thiab lub tsev menyuam. Nws koom nrog cov lus teb inflammatory thiab ua haujlwm raws li tus neeg nruab nrab ntawm khaus. Basophils thiab mast hlwb tsim cov tshuaj histamine, thiab histamine nce permeability ntawm capillaries rau cov qe ntshav dawb thiab cov protein tsim nyog los ua haujlwm tawm tsam cov kab mob. Yuav kom ua tiav cov nyhuv ntawm histamine, nws yuav tsum tau khi rau G protein-coupled histamine receptors. Muaj plaub hom histamine receptors xws li H1, H2, H3, thiab H4. H1 thiab H2 yog tam sim no nyob rau hauv associative nrog lub hauv paus paj hlwb thiab periphery. Li no, qhov sib txawv ntawm H1 thiab H2 receptors feem ntau nyob nrog lawv cov txheej txheem ntawm kev ua.
H1 Receptors yog dab tsi?
Histamine H1 receptor lossis H1 receptor yog ib qho ntawm plaub histamine binding receptors, uas yog G protein-coupled receptor. Qhov no yog lub ntsiab receptor uas tsim cov tsos mob thaum muaj kev tsis haum tshuaj. Nws yog ib qho protein zoo li heptahelical transmembrane molecule. Yog li, nws muaj peev xwm hloov cov teeb liab los ntawm ib puag ncig sab nraud mus rau intracellular thib ob tub txib los ntawm G protein-coupled tshua.
Daim duab 01: H1 Receptors
Ntxiv mus, qhov dav dav ntawm H1 receptors tuaj yeem pom ntawm qhov chaw ntawm lub cev, tshwj xeeb tshaj yog nyob rau hauv cov leeg nqaij. Sib nrug los ntawm lub periphery, H1 receptors nyob rau hauv lub adrenal medulla, vascular endothelium, lub plawv thiab lub hauv nruab nrab lub paj hlwb, thiab lwm yam. Lub zog kho los ntawm H1 receptor bindings yog ib tug contraction ntawm du nqaij, nce nyob rau hauv capillary permeability, mediating neurotransmission nyob rau hauv lub CNS, etc.
H2 Receptors yog dab tsi?
H2 receptor yog lwm histamine binding receptor, uas yog Gs protein-coupled receptor. Thaum no receptor-stimulated, los ntawm kev ua kom cov adenylyl cyclase, nws ua rau kom intracellular concentration ntawm cAMP nyob rau hauv ntau cov ntaub so ntswg. Qhov dav dav ntawm H2 receptors tuaj yeem pom nyob rau hauv lub hauv nruab nrab lub paj hlwb tshwj xeeb tshaj yog nyob rau hauv lub hlwb. Receptor concentration yog siab nyob rau hauv basal ganglia, hippocampus, amygdala thiab cerebral cortex.
Daim duab 02: H2 Receptors
Hypothalamus thiab cerebellum muaj qhov tsis tshua muaj siab ntawm H2 receptors. Tsis tas li ntawd, H2 receptors tam sim no nyob rau hauv parietal hlwb nyob rau hauv lub plab. Nws yog lub luag haujlwm rau kev tswj cov qib gastric acid. Thiab kuj H2 receptors tuaj yeem pom nyob rau hauv lub plawv, lub tsev menyuam thiab vascular du leeg hlwb. Thaum kev khi ntawm histamine rau H2 receptors blocks, nws tuaj yeem txo cov kua qaub uas ua los ntawm lub plab. Li no, H2 receptor agonists yog cov H2 blockers nrov uas siv los kho duodenal ulcers, gastric ulcers, Zollinger -Ellison kab mob thiab lwm yam.
Dab tsi zoo sib xws ntawm H1 thiab H2 Receptors?
- H1 thiab H2 receptors yog G protein-coupled receptors.
- Histamine khi nrog ob qho tib si receptors.
- YLawv yog cov protein.
- Tsis tas li, ob qho tib si receptors nyob hauv ntau qhov chaw ntawm lub cev.
- Feem ntau, lawv tau nthuav dav hauv lub hlwb tsiaj.
- Tsis tas li ntawd, ob qho tib si kho cov tshuaj histamine.
Qhov txawv ntawm H1 thiab H2 Receptors yog dab tsi?
H1 thiab H2 receptors yog ob hom histamine binding receptors uas siv los tawm tsam cov tshuaj histamine. Qhov sib txawv ntawm H1 thiab H2 receptors feem ntau yog nyob rau hauv cov txheej txheem ntawm txhua tus receptors. H1 receptors ob peb nrog Gq / 11 stimulating phospholipase C, thaum H2 receptors cuam tshuam nrog Gs kom qhib adenylyl cyclase. Lwm qhov sib txawv ntawm H1 thiab H2 receptors yog tias H1 receptors yog lub luag haujlwm tseem ceeb rau lub moos sab hauv thaum H2 receptors yog lub luag haujlwm rau kev tswj hwm ntawm lub plab acid.
Cov ntawv qhia hauv qab no qhia qhov txawv ntawm H1 thiab H2 receptors hauv daim ntawv teev npe.
Summary – H1 vs H2 Receptors
Ob leeg H1 thiab H2 receptors yog rhodopsin-zoo li G protein-coupled receptors. Lawv kho qhov kev txiav txim ntawm histamine hauv kev tsis haum tshuaj thiab ntau lwm yam kev xav ntawm lub cev. Histamine khi rau plaub histamine receptors ntawm lawv H1 thiab H2 yog tam sim no nyob rau hauv lub hauv paus paj hlwb. Yog li, H1 receptor khub niam txiv rau Gq / 11 stimulating phospholipase C, whereas H2 receptor cuam tshuam nrog Gs kom qhib adenylyl cyclase. Tsis tas li ntawd, H1 receptor feem ntau koom nrog hauv kev tswj hwm ntawm lub voj voog pw tsaug zog thaum H2 receptor feem ntau koom nrog kev txhawb nqa ntawm parietal hlwb kom zais cov kua qaub. Qhov no yog qhov txawv ntawm H1 thiab H2 receptors.
