The Mechanism of Action of Muscarinic Receptor Antagonists in Preventing Axial Myopia [ 2001 - 2003 ]

Research Grant

Researchers: Prof Neville Mcbrien (Principal investigator) ,  Charles Cottriall

Brief description Myopia (short-sightedness) is the most common refractive error and is due to the eye being too long and, if uncorrected, results in blurred distance vision. Approximately 30% of the population in developed countries, such as Australia, suffer from myopia. In a significant minority of individuals with high degrees of myopia, it is a sight threatening condition and a leading cause of blindness. It has been found that the pharmacological agent, atropine, is effective in preventing myopia in children and in animal models of myopia. However the side effects of blurred vision at near, glare from dilated pupils and the unknown long term effects of chronic atropine treatment have prevented this approach to myopia control from becoming an established treatment in children. It was originally thought that the drug worked by preventing the eye from accommodating for near objects, however it has now been shown that atropine does not to work by this mechanism, but rather by another non-accommodative mechanism. The aim of this project is to determine the mechanism of action of this class of drugs (known as muscarinic antagonists) in preventing myopic eye growth. The project will investigate in which ocular tissues the various subtypes of muscarinic receptors sensitive to these drugs are located and how these are changed in myopic eyes. It will also determine the specific receptor subtype these drugs act on and whether these drugs inhibit eye growth in myopia by altered retinal signalling activity. The results from this study will elucidate the mechanism and route of action of muscarinic antagonists in preventing myopic eye growth. These findings will advance the probability of developing an effective selective muscarinic antagonist drug to use for the prevention of axial myopia without the side effects associated with the broad-band antagonist atropine. The development of such drugs will have a major economic benefit to the Australian population.

Funding Amount $AUD 242,545.90

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant