Acetylcholine striatal neurons

Acetylcholine. Most of the acetylcholine in the basal ganglia is found in the striatum, as the neurotransmitter of the large spiny interneurons, which account for about 3% of all striatal neurons. Both muscarinic and nicotinic cholinergic receptors are found in the striatum. Postsynaptic muscarinic receptors may inhibit transmitter release from... 

Figure 5.6b represents two possible mechanisms of interaction between dopamine and acetylcholine. Inhibitory dopaminergic ami excitatory cholinergic neurons either synapse onto the same striatal neuron, or there is an intermediary cholinergic interneuron in the striatum... 

HT3 receptor agonists have been shown to enhance the release of endogenous dopamine from striatal slices [14] and to reduce acetylcholine release from sections of rat entorhinal cortex [15]. Furthermore, there are several electrophysiological techniques using a variety of neurones, including those in the gut [25] and primary cultures of brain tissue [26] which respond to 5-HT3 agonist stimulation. 

Pich EM, Paghusi SR, Tessari M, Talabot-Ayer D, Hooft v H, Chiamulera C (1997) Common neural substrates for the addictive properties of nicotine and cocaine. Science 275 83-86 PidopUchko VI, DeBiasi M, Williams JT, Dani JA (1997) Nicotine Activates and Desensitizes Midbrain Dopamine Neurons. Nature 390 401 04 PietUa K, Ahtee L (2000) Chronic nicotine administration in the drinking water affects the striatal dopamine in mice. Pharmacol Biochem Behav 66 95-103 Puttfarcken PS, Jacobs I, Faltynek CR (2000) Characterization of nicotinic acetylcholine receptor-mediated [ H]-dopamine release from rat cortex and striatum. Neuropharmacology 39 2673-2680... 

Dopamine is a catecholamine (see Chapter 10 and Fig. 31.2) whose actions are mediated by dopamine receptors that are classified as Dj-like (Dj, D5) or D2-like (D2, D3, D4). Dopamine actions on Dj receptors exert an excitatory effect, whereas the actions of dopamine on D2 receptors inhibit neuronal activity. The loss of striatal dopamine produces an imbalance in information processing in the neostriatum that modifies transmission in other basal ganglia regions. Also important in neural transmission are the striatal interneurons that are found within the confines of the striatum, that use the excitatory neurotransmitter acetylcholine, and that modulate the activity of striatal output neurons. 

Brown DA, Pilippov AK, Branard EA (2000) Inhibition of potassium and calcium currents in neurons by molecularly-defined P2Y receptors. J Auton Nerv Sys 81 31-6 Brown SJ, James S, Reddington M et al (1990) Both Ai and A2a purine receptors regulate striatal acetylcholine release. J Neurochem 55 31-8... 

Kirk IP, Richardson PJ (1994) Adenosine A2a receptor-mediated modulation of striatal [3H]GABA and [3H]acetylcholine release. J Neurochem 62 960-6 Koch H, von Ktigelgen I, Starke K (1997) P2-receptor-mediated inhibition of noradrenaline release in the rat hippocampus. Naunyn-Schmiedeberg s Arch Pharmacol 355 707-15 Koch H, von Ktigelgen I, Starke K (1998) P2-receptor-mediated inhibition of noradrenaline release in the rat pancreas. Naunyn-Schmiedeberg s Arch Pharmacol 357 431 10 Koizumi S, Inoue K (1997) Inhibition by ATP of calcium oscillations in rat cultured hippocampal neurones. Br J Pharmacol 122 51-8... 

The 5-HT4 receptors modulate the activities of channels and transporters by increasing cAMP levels. These include activation of L-type Ca2+ channels (326), chloride currents in human jejunal mucosa and rat distal colon (330,331), and the If pacemaker current in atrial myocytes (332) and stimulation of aldosterone release from the adrenal glands (333,334), striatal dopamine release (324), hippocampal and frontal cortex acetylcholine release (335,336), and hippocampal 5-HT release (337). 5-HT4 receptors also inhibit various channels, including a KV3.2-like delayed rectifier K+ channel (303), a voltage-activated K+ channel in colliculi neurons (320,338), a Ca2+-activated, afterhyperpolariz-ing, and K+ current in hippocampus (325). 

Gerfen, 2004). The patch compartments of the striatum are characterized by low levels of acetylcholine and high levels of various opiates and substance P. The matrix compartment is characterized by cholinergic and somatostatin-containing neurons. Anatomically, corticostriatal and thalamostriatal projections are closely associated with the striatal matrix, while projections from limbic structures, such as the hippocampus and the amygdala, primarily innervate striatal patches. 

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