March 5, 2012

Coagulation Cascade

Looks like the London Underground map. The coagulation cascade is an amazing thing. Perhaps a little hyperactive, but it keeps us alive long enough to procreate. Therein lies the problem: humans were never really supposed to leave beyond their twenties or thirties. We used to live in a pretty tough world before easy chairs and microwave dinners extended our lives into the sixties and seventies. Consequently, we end up with heart attacks because our coagulation system has a hard time telling when we are bleeding versus when we have to much plaque on our arteries (which, to blood, looks like we are bleeding). I heard a doctor once say that hemophilia was just nature (or God; take your pick) trying new things. Hemophiliacs don't usually die of heart attacks...of course, they have other major issues, but the point is relevant. Same with sickle cell anemia: those with the recessive trait have good resistance to Malaria but poor life expectancy.   
illustration of the human coagulation cascade