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==Farmakologi==
===Farmakodinamika===
Meklizin merupakan antagonis pada reseptor H1H<sub>1</sub> (Ki''K''<sub>i</sub> = 250 nM).<ref>{{cite journal | vauthors = Tran VT, Chang RS, Snyder SH | title = Histamine H1 receptors identified in mammalian brain membranes with [183H]mepyramine | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 75 | issue = 12 | pages = 6290–6294 | date = December 1978 | pmid = 282646 | pmc = 393167 | doi = 10.1073/pnas.75.12.6290 | doi-access = free }}</ref> Obat ini memiliki efek antikolinergik, depresan [[sistem saraf pusat]], dan [[anestesi lokal]]. Efek [[antimuntah|antiemetik]] dan antivertigonya belum sepenuhnya dipahami, tetapi sifat antikolinergik sentralnya turut berperan. Obat ini menekan rangsangan labirin dan rangsangan [[sistem vestibular]], dan dapat memengaruhi zona pemicu kemoreseptor meduler.[9]<ref name="Houston_2022" /> Obat ini terbukti mengurangi besarnya refleks vestibulo-okular pada relawan yang sehat.[19] Pada saat yang sama, obat ini ditemukan hanya memiliki efek kecil (dan tidak signifikan secara statistik) pada sensitivitas gerakan utrikulus.[19]<ref name="weerts">{{cite journal | vauthors = Weerts AP, De Meyer G, Pauwels G, Vanspauwen R, Dornhoffer JL, Van de Heyning PH, Wuyts FL | title = Pharmaceutical countermeasures have opposite effects on the utricles and semicircular canals in man | journal = Audiology & Neuro-Otology | volume = 17 | issue = 4 | pages = 235–242 | date = 2012 | pmid = 22517315 | doi = 10.1159/000337273 }}</ref> Sama seperti mabuk gerak yang muncul dari perbedaan antara beberapa indra, meklizin kemungkinan besar memengaruhi berbagai mekanisme sensorik yang terkait dengan gerakan diri sendiri sambil membiarkan respons vestibular inti tetap utuh.[20]<ref name="weerts"/> Much as motion sickness arises from a discrepancy between multiple senses, meclizine most likely affects a wide array of sensory mechanisms related to self-motion while leaving the core vestibular response intact.<ref>{{cite journal | vauthors = Wibble T, Engström J, Verrecchia L, Pansell T | title = The effects of meclizine on motion sickness revisited | journal = British Journal of Clinical Pharmacology | volume = 86 | issue = 8 | pages = 1510–1518 | date = August 2020 | pmid = 32077140 | pmc = 7373708 | doi = 10.1111/bcp.14257 | doi-access = free }}</ref>
Meklizin juga dilaporkan sebagai [[antagonis dopamin]] lemah pada reseptor mirip D<sub>1</sub> dan mirip D<sub>2</sub>{{citation needed|date=September 2015}} tetapi tidak menyebabkan [[katalepsi]] pada tikus, mungkin karena aktivitas antikolinergiknya.<ref name=Haraguchi_1997>{{cite journal | vauthors = Haraguchi K, Ito K, Kotaki H, Sawada Y, Iga T | title = Prediction of drug-induced catalepsy based on dopamine D1, D2, and muscarinic acetylcholine receptor occupancies | journal = Drug Metabolism and Disposition | volume = 25 | issue = 6 | pages = 675–684 | date = June 1997 | pmid = 9193868 | url = http://dmd.aspetjournals.org/cgi/pmidlookup?view=long&pmid=9193868 | access-date = 12 June 2014 | url-status = dead | archive-url = https://web.archive.org/web/20210828114146/https://dmd.aspetjournals.org/content/25/6/675.long | archive-date = 28 August 2021 }} "Catalepsy was assessed by the bar method: the front paws were gently placed on a horizontal metal bar with 2 mm diameter suspended 4 cm above, and the length of time the mouse maintains this abnormal posture was measured." </ref> Obat ini tidak memengaruhi penyerapan kembali [[dopamin]] atau [[serotonin]].<ref>{{cite journal | vauthors = Oishi R, Shishido S, Yamori M, Saeki K | title = Comparison of the effects of eleven histamine H1-receptor antagonists on monoamine turnover in the mouse brain | journal = Naunyn-Schmiedeberg's Archives of Pharmacology | volume = 349 | issue = 2 | pages = 140–144 | date = February 1994 | pmid = 7513381 | doi = 10.1007/BF00169830 }}</ref>
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