Viagra is tested against the leading cause of blindness human

In partnership with Israeli university, veterinary Jaboticabal, in São Paulo, drug tests devoted to treatment of erectile dysfunction against glaucoma, the leading cause of vision loss in dogs and humans. Research is conducted by the College of Agricultural Sciences and Veterinary of the UNESP. The aim of this study is to evaluate the possible beneficial effect of sildenafil, which is the generic name of viagra and whose sales success as a treatment for erectile dysfunction in men.

The idea of ​​using a drug for male impotence to treat the leading cause of human blindness arose from informal reports made by urologists from various countries over the years, explains veterinarian José Luiz Laus, researcher at the Faculty of Agricultural Sciences and Veterinary of the UNESP. According to him, some patients say that after you start using Viagra, start to see better, he says.

For the study, glaucoma was induced experimentally in rabbits. The animals were examined with an eye unit - the same used in people - to assess the health of the retina, in the traditional examination of the fundus.

Glaucoma affects about 1% of dogs and is the leading cause of blindness in dogs, the vet says Ofri Ron Israeli, Hebrew University of Jerusalem, Laus partner in the experiment. Both these animals and the people who have chronic ocular hypertension, the conventional drugs are failing to prevent loss of vision, precisely because they are focused on reducing the pressure within the eye, the expert explains. Hence the need to develop new drugs to treat this form of the disease, he says. That's what we do with sildenafil.

Ron Ofri comes to Jaboticabal in August to kick off a research project with the group of Jose Luiz Laus, a partnership made possible by an agreement, created this year between FAPESP and the Hebrew University of Jerusalem. But they both know a long time. And Israel is encouraged with the results obtained by experiments with rabbits in Brazil over the past two years.

While we have not completed the statistical analyzes of data, you could say that the drug improves the oxygenation of the retina, because more blood passes through it, describes Laus. We do not know the mechanism by which this occurs. The hypothesis is that there is a dilation of the ophthalmic artery [which supplies blood to the retina].

If so, it would be a mechanism similar to the drug produces in the corpora cavernosa of the penis, which, more irrigated by blood, remains erect. Although the rabbits studied in the laboratory of Laus were all males, it ensures that no abnormal behavior was observed inside the cages. Because, if so, had to have females around, he says.

Example <b> aspirin </ b>

For the researcher Jaboticabal, not surprising that one day Viagra might treat an eye disease, possibly in the form of eye drops. This is normal in pharmacology, said. The classic case is that of aspirin, which was discovered as an analgesic, but whose use is now more important as blood anticoagulant in the prevention of stroke, heart attack and stroke.

Sildenafil is himself an example of pharmacological versatility. In male impotence, the drug is used to treat pulmonary hypertension, including children. Studies suggest it may also be useful in combating the malaise caused by the altitude. In 2007, Harvard awarded an Argentinean researcher Ig Nobel prize - a satire for the Nobel Prize - by showing that Viagra combat the effects of jetlag in hamsters.

In the new phase of research, the Laus Group will study the effect of the drug in rats with glaucoma. The goal now is to evaluate the blood supply to a specific part of the retina called the optic disc, which is precisely where the optic nerve emerges. To do this, count on the expertise of Israeli counterpart in advanced analysis of this delicate nerve tissue.

If in the case of the rabbit eye exam was not invasive, rats biopsy is required. We do not know if the material will be analyzed here or in Israel. Let's decide this when Ron arrived, Laus account. Despite the enthusiasm, the Brazilian pragmatism makes clear his way of doing science: I prefer to work to prove that my assumptions are wrong, he says. This produces more reliable results.

Excited about the next trip, his Israeli counterpart does not hide that their expectations go beyond the scientific realm. My goal is to know the infrastructure of the lab, discuss the schedule and details of research, and a caipirinha by the success of our project!

With information <i> Unesp </ i>

• Tweet