However, the traditional controversy between the vascular and neuronal theories was scientifically settled in 2002 when it was discovered that brain topical administration of the vasoconstrictor polypeptide endothelin 1 is a highly effective trigger of SD in rodents in vivo and that endothelin 1 has this effect because of its vasoconstrictor properties, which cause SD in a concentration-dependent manner mediated by an imbalance between energy supply and demand of neurons [10]. The gene discussed is EDN1; the disease is Salla disease.