Researchers from the Massachusetts Institute of Technology (MIT) report in the Journal of Neuroscience that a chemical receptor in the brain associated with learning and memory might also play a vital role in fetal development of the respiratory system. The study proposes a possible connection to Sudden Infant Death Syndrome (SIDS) and preemie problems.
Dr. Chi-Sang Poon, a Principal Research Scientist in the Harvard-MIT Division of Health Sciences and Technology (HST) and first author of the paper, with co-authors  Zhongren Zhou, a former HST postdoctoral fellow, and Jean Champagnat of the Centre National de la Recherche Scientifique in France, states that it would be sensible for pregnant women to avoid prolonged exposure to substances that stimulate this receptor. Such substances include alcohol, PCP (angle dust) and come common anesthetic and analgesic drugs such as ketamine. Their work was supported by the National Institutes of Health, the Office of Naval Research, and the Human Frontier Science Program.

Dr. Poon noted that mutant mice lacking the receptor could not breathe or suck well. These symptoms are common in premature babies and are risk factors for Sudden Infant Death Syndrome. Their study assumes a possible correlation between abnormal activity receptors and problems in newborns, although further studies have yet to clarify this theory.
A surprise finding in the study and research, the lack of this receptor also led to high amounts of long term synaptic depression (LTD), which is an activity linked to learning and memory. They found that the increased LTD was found in the brainstem, and area in the brain not usually linked with high level functions.
The brainstem coordinates lower behaviors like breathing and other vital functions, Dr. Poon explains. The fact that there was found to be learning activity in the brainstem supports his argument that there is more intelligence going on subconsciously. The NMDA receptor has been of interest to scientists studying learning and memory. The N-methyl-D-aspartate (NMDA) receptor is the key to the communication of a chemical signal between two nerve cells. That process, repeated between many cells is how a signal is propagated through the brain.
The study, however, had an unexpected hitch – the animals died soon after birth. This was later solved by restricting the NMDA knockout to a specific area of the brain rather than throughout the organ. The team, though, interested in why the first animals were dying, explored a number of reasons. They eventually found the reason, that the lack of NMDA receptors during the prenatal development led to fatal respiratory distress. Normal newborn mice treated with drugs that block NMDA receptor activity did not have any respiratory problems.
Dr. Poon says that this is the first indication that prenatal development of specific regions in the brain controlling vital functions is very dependent on NMDA receptor activity. A lack of NMDA receptor activity in the fetus could affect newborns’ breathing after birth. Also, the unexpected increase in LTD in the brainstems of the mutant mice shows that learning and memory at a subconscious level could profoundly influence our vital functions. READ ARTICLE