background : patients with alzheimer's disease (ad) reportedly hibit hypersensitivity to much diluted tropicam solution (0.005%), a m4 muscarinic receptor antagonist. therefore aocular application of 0.005% tropicamide ma be useful for screening dementia. the aim of this study was to simplify the pupil response test by using a new image analyzing system, which consists of a cheap, simple, and e...

To investigate the autonomic components of the pupillary light reflex in humans, we used infrared pupillometry combined with a partial local cholinergic (tropicamide) or alpha-adrenergic (thymoxamine) blockade. The pupillary response curve was analyzed using parameters identical or similar to those employed previously to study the autonomic components of the pupillary light reflex. Tropicamide ...

Tropicamide (muscarinic receptor antagonist) and phenylephrine (α-adrenergic receptor agonist) are commonly used to dilate the pupils by topical application. These two eye drops are often used, singly or in combination, to dilate the pupil and perform acute light-evoked physiological experiments (electroretinography, for example), before and after intravitreal injections of pharmacological agen...

The mydriatic response to eyedrops of the anticholinergic agent tropicamide at very low concentration (0.01%) has been studied in people with Down's syndrome. By comparison with healthy subjects people with Down's syndrome had responses approximately three times greater, suggesting a peripheral imbalance between cholinergic and adrenergic autonomic influences.

M2 receptors have long been believed to be the only functional subtype of muscarinic acetylcholine receptor (mAChR) in the heart, although recent studies have provided evidence for the presence of other subtypes. We performed a detailed study to clarify this issue. In the presence of tetramethylammonium (1 microM to 10 mM), a novel K+ current with both delayed rectifying and inward rectifying p...

Three researchers share this year ́s Nobel Prize in Chemistry: Dr. Yves Chauvin at the Institut Français du Pétrole, Rueil-Malmaison, France; Professor Robert H. Grubbs, California Institute of Technology, Pasadena, California, USA and Professor Richard R. Schrock, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. The Royal Swedish Academy of Sciences citation runs “for the d...