Acetylcholine (ACh) was the first neurotransmitter identified as a regulator of mammalian circadian rhythms. When injected in vivo, cholinergics induced biphasic clock resetting at night, similar to nocturnal light exposure. However, the retinohypothalamic tract connecting the eye to the suprachiasmatic nucleus (SCN) uses glutamate (GLU) to transmit light signals. We here resolve this long-stan...

ÐThe function of the cholinergic system is known to change during normal aging and in pathological conditions such as Alzheimer's disease. The present study was designed to assess, within the same group of old animals, the behavioral, electrophysiological and neurochemical effects of chronic treatment with agents that increase the function of the cholinergic system through both muscarinic and n...

Studies demonstrate that some colon cancers possess receptors for various gastrointestinal hormones or neurotransmitters, the occupation of which can affect growth. These results are limited because frequently only a small number of tumors are studied, only 1 or 2 receptors are sought, and the effect on cell function is not investigated. In the present study, 10 recently characterized human col...

BACKGROUND Airway instrumentation can evoke upper airway reflexes including bronchoconstriction and cough which can cause serious complications including airway trauma, laryngospasm or bronchospasm which may in turn lead to difficulty with ventilation and hypoxemia. These airway events are mediated in part by irritant-induced neuronal modulation of airway tone and cough responses. We investigat...

Basic mechanism of action of organophosphates (OP)/nerve agents is based on acetylcholinesterase (AChE) inhibition and subsequent accumulation of neuromediator acetylcholine at the cholinergic synapses, either peripheral or central, causing cholinergic hyperstimulation and development of symptoms of poisoning, followed by metabolic dysbalance and, without eff ective prophylaxis/treatment leadin...

Studies demonstrate that some colon cancers possess receptors for various gastrointestinal hormones or neurotransmitters, the occupation of which can affect growth. These results are limited because frequently only a small number of tumors are studied, only 1 or 2 receptors are sought, and the effect on cell function is not investigated. In the present study, 10 recently characterized human col...

Active ion transport by the airway epithelium plays an important role in maintaining the effective defense mechanisms of the airway by regulating the volume and composition of the airway fluid. We investigated the abilities of adrenergic agents, cholinergic agents, and chemical mediators to modulate ion transport in canine tracheal epithelium, using Ussing-type chambers. Transepithelial electri...

Transgenic mice over-expressing mutant human amyloid precursor protein (PDAPP mouse) develop several Alzheimer’s disease (AD)-like lesions including an age-related accumulation of amyloid-?-containing neuritic plaques. Although aged, heterozygous PDAPP mice also exhibit synaptic and glial cell changes, that is characteristic of AD pathology, no evidence of neurodegeneration has been observed. T...

Introduction: Nitric Oxide is an important endogenous compound that acts as bronchodilator in trachea. Electromagnetic fields (EMF) affect nitric oxide level in different tissues. The interaction of nitrergic and cholinergic systems in airways has been reported. Therefore, the present study was performed to evaluate the interaction of cholinergic and nitrergic systems in the trachea of rats ...