Muscarinic cholinergic

Nicotinic Receptor Agonists. There has been significant activity in the development of muscarinic cholinergic receptor agonists for dementia. In addition, agents that interact with nicotinic cholinergic receptors may also have therapeutic value. Nicotinic receptors have been reported to be... 

The mink Mustela vision) is a piscivorous mammal that also has been exposed to relatively high dietary levels of methyl mercury in North America in recent times. In a Canadian study, mink trapped in Yukon territory, Ontario, and Nova Scotia were analyzed for levels of mercury and abundance of muscarinic, cholinergic and dopaminergic receptors in the brain (Basu et al. 2005). A correlation was found between total Hg levels and abundance of muscarinic receptors, but a negative correlation was found between total Hg and abundance of dopaminergic receptors. Thus, it was suggested that environmentally relevant concentrations of Hg (much of it in methyl form) may alter neurochemical function. The highest levels of mercury contamination were found in mink from Nova Scotia that had a mean concentration of total Hg of 5.7 pg/g in brain, 90% of which was methyl mercury. 

Ward, D., and Trevor, A. Phencyclidine-induced alteration in rat muscarinic cholinergic receptor regulation. ux U Pharmacol 74 189-193, 1981. 

Motion sickness is caused by stimulation of the vestibular system. This area contains many histaminic (Hj) and muscarinic cholinergic receptors. The higher brain (i.e., cerebral cortex) is affected by sensory input such as sights, smells, or emotions that can lead to vomiting. This area is involved in anticipatory nausea and vomiting associated with chemotherapy. 

Antihistamines are commonly used to prevent and treat nausea and vomiting due to motion sickness, vertigo, or migraine headache.1,17 Their efficacy is presumably due to the high concentration of histamine (Hx) and muscarinic cholinergic receptors within the vestibular system. Similarly to scopolamine, antihistamines such as diphenhydramine and... 

Monoamine oxidase inhibition Serotonin reuptake inhibition Norepinephrine reuptake inhibition Dopamine reuptake inhibition a2-Adrenergic receptor blockade Serotonin-2A receptor blockade Serotonin-2C receptor blockade Serotonin-3 receptor blockade op-Adrenergic receptor blockade Histamine-1 receptor blockade Muscarinic cholinergic receptor blockade... 

Cory-Slechta DA, Pokora MJ. 1995. Lead-induced changes in muscarinic cholinergic sensitivity. Neurotoxicology 16 33-348. 

Gronier, B. Rasmussen, K. (1998). Activation of midbrain presumed dopaminergic neurones by muscarinic cholinergic receptors an in vivo electrophysiological study in the rat. Br. J. Pharmacol. 124, 455-64. 

ACh regulates the cortical arousal characteristic of both REM sleep and wakefulness (Semba, 1991, 2000 Sarter Bruno, 1997, 2000). Medial regions of the pontine reticular formation (Figs. 5.2 and 5.7) contribute to regulating both the state of REM sleep and the trait of EEG activation. Within the medial pontine reticular formation, presynaptic cholinergic terminals (Fig. 5.1) that release ACh also are endowed with muscarinic cholinergic receptors (Roth et al, 1996). Autoreceptors are defined as presynaptic receptors that bind the neurotransmitter that is released from the presynaptic terminal (Kalsner, 1990). Autoreceptors provide feedback modulation of transmitter release. Autoreceptor activation... 

EEG slow waves. The differential EEG and ACh responses to dialysis delivery of AF-DX 116 (M2/M4) versus pirenzepine (M1/M4) supports the conclusion that, in B6 mouse, postsynaptic muscarinic receptors of the Ml subtype form one receptor mechanism by which ACh activates the EEG (Douglas et al, 2002a). The data summarized in Fig. 5.11 provide direct measures of G protein activation in basal forebrain and prefrontal cortex by muscarinic cholinergic receptors (DeMarco et al, 2004). The in vitro data of Fig. 5.11A indicate the presence of functional muscarinic receptors in regions of B6 mouse prefrontal cortex where in vivo microdialysis studies (Douglas et al, 2002a, b) revealed modulation of ACh release and EEG by pre- and postsynaptic muscarinic receptors (Figs. 5.9 and 5.10). 

Scopolamine A muscarinic cholinergic receptor antagonist that has amnesic side effects. 

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