I will do my part to see that this subject is not dropped. It is much too hot to allow that to happen.

The little bit of recent research that I have run across on the BBB relates to a normal intracellular protein of endothelial cells called glycoprotein C, or GPC. As most of you know from earlier posts, the endothelial cells line the insides of the circulatory system and form the BBB, assuming that there are no gaps between them. GPC protein is a main participant in a process in which exogenous substances that are able to penetrate the cell membrane of these cells are pumped back out into the circulatory system.

In the past, GPC has been studied most intensely in efforts to overcome its action since it tends to prevent chemotherapy drugs from reaching their cancer cell targets.

The one or two studies that I saw concerned what are called polymorphic forms of the human gene for GPC. Polymorphisms are different forms of the same gene which vary only slightly in structure from each other, and it is common for normally functional genes to exhibit such differences. What these researchers were looking for was an association between PD and a less common GPC polymorphism which was known to result in the production by endothelial cells of a smaller amount of the protein than is produced from a different, more common polymorphism of the protein. Since the less common form was already known to be equally active with the more common form, it was not a matter of it being "crippled", or less functional.

Unfortunately, they were not able to show a statistically significant association between the presence of the suspect GPC gene and the presence of PD.

Maybe some other aspect of the action of this protein's activity can be related to PD, such as the selectivity with whichl it "pumps" different subsances, e.g. H pylori endotoxins. Hope springs eternal!!!

If anyone is intersted, I can post the references on these studies tomorrow when I am back on my office computer.

Robert