By Todd Zwillich

WASHINGTON (Reuters Health) - Medical chemists in the US and Europe are trying to treat type 2 diabetes by targeting receptors for glucagon, a hormone that raises blood sugar levels when they get too low. The findings were reported at the American Chemical Society meeting here.

So far, cooperative research between one American pharmaceutical company and another in Denmark have produced three similar molecules that researchers say can selectively bind to glucagon receptors in experimental animals. The molecules could provide a new way to keep blood glucose (sugar) levels down in people with type 2 (or insulin-resistant) diabetes. Type 2 diabetes usually occurs in adults and sometimes can be controlled with a combination of diet and exercise; people with the condition lose their sensitivity to insulin, which results in excess blood sugar.

Finding a molecule to occupy glucagon receptors is one possible way to prevent elevated glucose.

``The molecule fits into the receptor, which we think might be shaped like a funnel,'' said Dr. Anthony Ling, a researcher with California-based Agouron Pharmaceuticals. In one study, Ling and his colleagues injected rats with a compound that blocked glucagon receptors. Another group of animals received a placebo (inactive) injection. Fifteen minutes later, all of the animals were given glucose intravenously.

The animals given a placebo wound up with two to four times the level of glucose in the blood as those given a low and high dose of the receptor blocker. In a second study, Ling's team found that giving rats abdominal injections of a slightly different version of the compound reduced blood glucose levels.

A third version of the compound was studied by researchers from Novo Norkisk Pharmaceuticals in Denmark. Their molecule, which was engineered to be administered orally, managed to hold glucose levels constant in rats that were injected with glucagon.

The researchers remain tight-lipped about the timing of any possible human trials with glucagon receptor-blocking agents. But they are confident that the approach may provide a good alternative to currently available drugs for type 2 diabetes, which risk over-correction of blood sugar and causing too-low blood sugar--hypoglycemia--as a side effect.

``We've never seen any hypoglycemic animals. This may be a safer approach,'' Novo Nordisk researcher Peter Madsen told Reuters Health in an interview.

(From Yahoo)