The symptomatic effects of drug abuse are a result of alterations in the functioning of the following neurotransmitters or their receptors: acetylcholine, dopamine, gamma-aminobutyric acid, norepinephrine, opioids and serotonin. Anticholinergic drugs antagonize acetylcholine receptors. Dissociative drugs affect all transmitter sites. Opiates act on both opioid and adrenergic receptor sites. Psy...

In atrial and ventricular cells from hearts of hatched chicks, acetylcholine reduced the overshoot and the duration of action potentials recorded in normal Tyrode's solution (5.4 ITIM K). This effect of acetylcholine is attributed to inhibition of the slow inward current-dependent portion of the action potential because acetylcholine reduced the overshoot, rate of rise, and duration of the Ca/N...

Abstract: Background/Aim: Alzheimer’s disease (AD), a type of neurodegenerative disorder, possesses significant memory loss as one the cardinal manifestations. The pathophysiology AD includes increased accumulation A?, degeneration cholinergic activity and mitochondrial dysfunction. Nicotinic acetylcholine receptors (nAChRs) especially alpha7 nicotinic (?7 nAChRs) are widely distributed in brai...

The identification of the neuronal control of bone remodeling has become one of the many significant recent advances in bone biology. Cholinergic activity has recently been shown to favor bone mass accrual by complex cellular regulatory networks. Here, we identified the gene expression of the muscarinic and nicotinic acetylcholine receptors (m- and nAChRs) in mice tibia tissue and in osteocytic...

Exogenous application of acetylcholine elicits inward currents in hippocampal interneurons that are mediated via a-bungarotoxin-sensitive nicotinic acetylcholine receptors, but synaptic responses mediated via such receptors have never been reported in mammalian brain. In the present study, EPSCs were evoked in hippocampal interneurons in rat brain slices by electrical stimulation and were recor...

Cortical processing is strongly influenced by the actions of neuromodulators such as acetylcholine (ACh). Early studies in anaesthetized cats argued that acetylcholine can cause a sharpening of orientation tuning functions and an improvement of the signal-to-noise ratio (SNR) of neuronal responses in primary visual cortex (V1). Recent in vitro studies have demonstrated that acetylcholine reduce...

GABAergic interneurons have been shown to be a major target of cholinergic inputs to the hippocampus. Because these interneurons project to pyramidal neurons as well as other interneurons, activation of the cholinergic system is likely to produce a complex modulation of local inhibitory activity. To better understand the role of post-synaptic alpha7 nicotinic acetylcholine receptors in the hipp...

We examined the effect of zinc on rat neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes as simple heteromers of alpha2, alpha3, or alpha4 and beta2 or beta4. Coapplication of zinc with low concentrations of acetylcholine (</=EC(10)) resulted in differential effects depending on receptor subunit composition. The alpha2beta2, alpha2beta4, alpha3beta4, alpha4beta2, a...

Structure-function relationship studies of the m3 muscarinic acetylcholine receptor have recently identified a series of threonine and tyrosine residues (all located within the hydrophobic receptor core) that are critically involved in acetylcholine binding (Wess, J., Gdula, D., and Brann, M.R. (1991) EMBO J. 10, 3729-3734). To gain further insight into the functional roles of these amino acids...