Neuronal effects

With so many different neurosteroids with differing and even opposing neuronal effects, much will depend on their relative concentrations at any time and any evaluation of their function must take this into consideration. Hopefully the synthesis and use of appropriate antagonists will throw more light on the physiological role of steroids in the CNS and facilitate the development and clinical use of new neuroactive steroids (see Gasior et al. 1999). 

Bunney, B.S. Aghajanian, G.K. and Roth, R.H. Dopaminergic neurons Effect of antipsychotic drugs and amphetamine on single cell activity. 

Mihailescu, S., Guzman-Marin, R. Drucker-Colin, R. (2001). Nicotine stimulation of dorsal raphe neurons effects on laterodorsal and pedunculopontine neurons. Eur. Neuropsychopharmacol. 11, 359-66. 

McLean, P. J., Kawamata, H., Ribich, S. and Hyman, B. T. (2000). Membrane association and protein conformation of alpha-synuclein in intact neurons. Effect of Parkinson s disease-linked mutations. J. Biol. Chem. 275, 8812-6. 

Carmeliet, P. and Storkebaum, E. Vascular and neuronal effects of VEGF in the nervous system implications for neurological disorders. Semin. Cell Dev. Biol. 13 39-53, 2002. 

Opioid effects on memory are consistent in humans and animal models (Braida et al. 1994 Saha et al. 1991). Verbal and visual memory are impaired by morphine one hour after oral administration (Hanks et al. 1995 Kerr et al. 1991). These could be due to direct neuronal effects of opioids, or perhaps through indirect effects on cholinergic transmission. However, in some animal paradigms morphine can enhance memory consolidation through indirect dopaminergic mechanisms (Castellano et al. 1994). 

In addition to vomiting and diarrhea, severe toxicity can occur with erroneous or intentional overdoses. These include cardiac arrythmias and atrial tachycardia with atrial-ventricular (AV) block. These effects are due to increased intracellular calcium. Hyperkalemia also occurs. Disturbances of cognitive function, including visual disturbances, delirium, and convulsion are also adverse effects resulting from neuronal effects. 

Sirois, J. E., Lei, Q., Talley, E. M., Lynch III, C., Bayliss, D. A. The TASK-1 two-pore domain fC channel is a molecular substrate for neuronal effects of inhalational anesthetics, The Journal of Neuroscience 2000, 20, 6347-6354. 

Todorovic SM, Lingle CJ (1998) Pharmacological properties of T-type Ca current in adult rat sensory neurons effects of anticonvulsant and anesthetic agents. J Neuro-phys 79 240-252... 

Kelly PH, Moore KE (1977) Mesolimbic dopamine neurons effects of 6-hydroxydopamine-induced destruction and receptor blockade on drug-induced rotation of rats. Psychopharmacology (Berl) 55 35-41. 

Schwarcz R, Pellicciari R (2002) Manipulation of brain kynurenines glial targets, neuronal effects, and clinical opportunities. J Pharmacol Exp Ther 303 1-10... 

In the literature dangerous for brain neurons effect of ROS was traditionally underestimated — one can believe that multi-step antioxidant system should provide reliable protection. Actually, antioxidants are able to remove toxic component of glutamate overloading and keep neurons viable. However, this point of view is under serious doubt because of both a multiple role of antioxidants in brain metabolism [1,38,52] and apparent absence of therapeutic effect of antioxidant protection [42]. 

HT3 receptors are of the fast-transmission intrinsic ion channel (cation) type (previously referred to as M receptors, since their neuronal effects were blocked by morphine). This multiunit receptor shows marked species-dependent differences in isoforms. Selective agonists include m-chlorophenylbiguanide (m-CPBG), 2-methyl-5-HT and 5-HTQ (trimethylserotonin, a quaternary salt of serotonin). 

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