Receptorium acetylcholini muscarinicum
Receptoria acetylcholini muscarinica (mAChR) sunt receptoria acetylcholini, complexus cum proteino G copulata formantes et sub haec canales ionticos vel nuntios secundarios excitant. Locata sunt mAChR in membranis neuronorum.
Adhuc subtypi quinque, M1 - M5, noti sunt.
Receptoriis muscarinicis munera sunt in cerebro at, per systema nervosum autonomicum in organis diversis ut in oculo[1], in apparatu circulatorio[2], in apparatu digestorio[3], in vesica urinaria[4].
In medicina morbi cum structuris muscarinicis coniuncti ope agonistarum vel antagonistarum tractari possunt.
Acetylcholinum et receptoria acetylcholini in genere
recensereAcetylcholinum (ACh) est substantia chemica minor, ex atomis carbonii septem constituta; massa molaris eius tantum 146.21 g/mol est. In organismis ACh virtutes neurotransmissor ostendit. Ex synapsibus cholinergicis ("praesynapticis") in fissuram synapticam emissum, ACh receptoria propria, cholinergica, nervi proximi ("postsynaptici") obsidet. Omnia receptoria in membrana cellulae invenitur, ea sunt proteina transmembranacea. Distinguitur greges duo receptoriorum acetylcholini, receptoria nicotinica et receptoria muscarinica. Effectus acetylcholini nominantur cholinergici. Substantiae, insuper receptoria acetylcholini stimulantes, cholinergicae vocantur, tales, receptoria acetylcholini inhibentes, anticholinergicae.
Natura receptoriorum muscarinicorum
recensereInveniuntur receptoria muscarinica in systemate nervoso centrali et in systemate nervoso autonomico[5]. Separantur quinque receptoria M1 - M5 nominata, quibus omnibus septem segmenta transmembranacea, quae in parte structura helicis ostendunt, sunt. Recipiunt neurotransmissor acetylcholinum (ACh) extra cellulam; deinde intra cellulam proteinum G incitant. Receptoria M1, M3, M5 cum proteino Gαq/11 (olim: Gq) coniuncta, at M2 et M4 cum Gαi/o (olim: Gi/Go).
Subtypi receptoriorum muscarinicorum
recensereAdhuc subtypi quinque descripti sunt: M1 - M5[6].
Receptorium M1
recensereNon raro receptorium M1 (M1R) neuronale vocatur. Inveniuntur M1R in gangliis autonomicis.
Receptorium M2
recensereInvenitur receptorium M2 in corde et in systemate nervoso centrali.
Receptorium M3
recensereInvenitur receptorium M3 in multis organiis internis, ut in vasibus sanguineis, oculis, glandulis salivariis, pulmonibus, apparatu digestorio, vesica urinaria
Receptorium M4
recensereInvenitur receptorium M4 in systemate nervoso centrali.
Receptorium M5
recensereInvenitur receptorium M5 in systemate nervoso centrali.
Notae
recensere- ↑ Mitchelson F. (2012). "Muscarinic Receptor Agonists and Antagonists: Effects on Ocular Function". Handbook of experimental pharmacology (208): 263-98
- ↑ Harvey R. D. (2012). "Muscarinic Receptor Agonists and Antagonists: Effects on Cardiovascular Function". Handbook of experimental pharmacology (208): 299-316
- ↑ Ehlert F. J., Pak K. J., Griffin M. T. (2012). "Muscarinic Agonists and Antagonists: Effects on Gastrointestinal Function". Handbook of experimental pharmacology (208): 343-74
- ↑ Sellers D. J., Chess-Williams R. (2012). "Muscarinic Agonists and Antagonists: Effects on the Urinary Bladder". Handbook of experimental pharmacology (208): 375-400
- ↑ Haga T. (2013). "Molecular Properties of Muscarinic Acetylcholine Receptors". Proceedings of the Japan Academy. Series B 89 (6): 226-56
- ↑ Eglen R. M. (Iul 2006). "Muscarinic Receptor Subtypes in Neuronal and Non-Neuronal Cholinergic Function". Autonomic & autacoid pharmacology 26 (3): 219-33
Nexus externi
recensere- Taylor P. et Brown J. H. (1999): Basic Neurochemistry: Molecular, Cellular and Medical Aspects. 6th edition