Basic Science - Important Questions for Spinal Cord Regeneration
The CNS is composed of the brain, spinal cord, eye and optic nerve. While it was once thought that CNS cells cannot regenerate, it has recently been shown that they can, but do not do so effectively in mammals. In order to understand why nerves do not grow properly under some conditions, it is first important to determine what actually happens when they grow. One important way to look at regeneration, therefore, is to carefully examine the processes of nerve growth and regeneration wherever they are most accessible to our current techniques. Consequently, many scientists study nerve cells in animals that one would not expect to have particular relevance to the human spinal cord - such as goldfish, frogs, or even the sea snail, Aplysia.
Despite the obvious differences between species within the animal world, experiments conducted in "simple" animals compared to the more complex animals can provide important answers to basic biological questions that will be helpful to answering human centered issues as well as questions about those specific species. These simple animal models provide relatively neat and uncluttered environments in which to study specific questions. The less complicated a theory is, and the fewer complicating variables there are when studying it, the more likely one is to be able to come up with a definitive result.
The human spinal cord is an incredibly complex organ. Proper spinal cord function is dependent upon an intricate interaction among individual cells, each of which has a specific function and a unique role in the CNS. The best way to study the unique roles of cells and their interactions with other cells is to develop simple animal models that enable one to isolate a particular cellular relationship rather than to try to sort out a multitude of relationships at the same time. Once those basic relationships are clearly understood, it will be possible to examine with some degree of understanding the complex Environment of several different processes occurring at the same time.
At the present time, scientists still do not understand clearly how a human spinal cord functions under normal conditions. Thus, one of the most pressing concerns today is to develop definitive answers to questions concerning basic CNS function. A second import-ant area to examine is that of cellular response to injury. How does the CNS respond to injury? Again, a good way to address this questions is to look at animal systems that do regenerate CNS cells. If scientists can determine how other animals accomplish what we would like to see in humans, then they can begin applying that knowledge to finding a cure for SCI.
It is important to realize that the goal of basic science research is to answer basic questions about biology. Once the answers to the most basic biological questions are found, then it will be necessary to determine how the various systems work together in animals and in humans. Much further down that road of course is the development of experimental treatment approaches to reverse the effects of SCI.
