The blood brain barrier is an absolutely vital intercellular defense mechanism in vertebrates and invertebrates. This system restricts the nervous system from contact with toxins, water soluble compounds and ionic imbalances present in the blood. Nerves in particular must be bathed in fluid of special ion concentrations and thus cannot have direct access to blood (which has a different constitution). The blood brain barrier is not always a blessing to life, as many drugs cannot cross this barrier to cure or relieve neurological diseases and syndromes. (This is especially true for AIDS). Insects too have a blood-brain barrier. Nevertheless, very little else is known about this system relative to the growing and metamorphosing insect larva. In many insect species, the larval stage is the longest life stage, and the one in which most economic damage is wrought. Once the dynamics of this barrier are understood in insects and its genesis, placement and extent, compromising the barrier may be possible. Insects without this barrier would die quickly of natural causes. It is likely there may be physical means and/or environmentally safe compounds that would transiently impair the barrier system in insects and so assist in population suppression. This latter goal would only be possible after a thorough structural and functional study has been made of the larval insect blood brain barrier as set forth in the studies.
