Light Could Make Paralyzed Limbs Move 63
Zothecula writes "In a study that could eventually restore movement to humans' paralyzed limbs, researchers at California's Stanford University have used light to induce muscle contractions in mice. A gene derived from algae was inserted into the mice, encoding a light-sensitive protein which adhered to their nerve cell surfaces. Scientists then placed an 'optical cuff' lined with tiny, inwards-facing LEDs around the mice's sciatic nerves. By penetrating those nerves with brief, high-intensity bursts of blue light, they were able to produce muscle contractions similar to those that would occur naturally. The technology is called 'optogenetics.'"
Re:Got ED? (Score:4, Informative)
2) the relaxation I was referring to was of the smooth muscle in the walls of the arteries leading to the penis
3) there isn't much regulation of bloodflow that takes place on the venous side (ie venous drainage is relatively constant). thus if you increase flow inward it will necessarily lead to pooling (ie erection)
the classic ED drugs all work by relaxing the arteries that flow toward the penis by inhibiting PDE5, a phosphodiesterase predominantly found in penis arteries. this increases cAMP levels, leaving to vasodilation and an erection. unfortunately these drugs aren't perfectly specific, and cause small amount of vasodilation throughout the body, along with a corresponding drop in blood pressure. this is why they tell you not to take the ED pills if you take other vasodilators like nitroglycerin.
if you could engineer a Gs (i was wrong in my earlier post when I said Gi, you want more cAMP not less) receptor that was light sensitive, and get it to express only in the penis artery smooth muscle.... and shine light through your skin to activate these receptors, it would work the same way.
obviously not an ideal way to treat a disorder. these light gated channels are probably only good for basic scientific research.