a tight BBB only allows certain drugs thru..mostly a function of
lipid solubility. For example, alcohol and anesthetics pass the
easiest.

In the case of the Zonulin channels, these would allow bacteria thru, and large water soluble substances and peptides. This would be the CNS version of "leaky gut syndrome". Leaky gut was always pooh poohed by doctors and now with the new information, that is no longer that controversial.

Some drugs like H2 antagonists, Zantac and Pepcid, pass the BBB more often in the elderly. They cause a delirium when that happens. That is one example of how the BBB changes with age.

Do you have any info on things that might simultaneously increase permeability of both BBB and gut? Given our slow GI motility that would seem to dump toxins into the bloodstream at the worst possible time.

We already know that stress opens the BBB. It works both ends of the street, it seems,


1: Curr Mol Med. 2008 Jun;8(4):299-312.

The effects of physical and psychological stress on the gastro-intestinal tract:
lessons from animal models.

Caso JR, Leza JC, Menchén L.

Sección de Gastroenterología, Servicio de Aparato Digestivo, Hospital General
Universitario "Gregorio Marañón", C/ Dr Esquerdo 46. 28007 Madrid, Spain.

Physical and psychological stresses are widely accepted as triggers and / or
modifiers of the clinical course of diverse gastrointestinal disorders such as
peptic ulcer, irritable bowel syndrome or inflammatory bowel disease. Growing
experimental evidence from a variety of models such as immobilization, thermal
injury or early maternal deprivation in laboratory animals uniformly supports the
ability of stress to induce the development of gastric ulcers, altered
gastrointestinal motility and ion secretion, and increased intestinal
permeability leading to the passage of antigens to the lamina propria and
bacterial translocation. Stress can also synergize with other pathogenic factors
such as Helicobacter pylori, non-steroidal anti-inflammatory drugs or
colitis-inducing chemicals to produce gastrointestinal disease. The brain-gut
axis provides the anatomical basis through emotions and environmental influences
modulate the gastrointestinal function through the regulation of gastrointestinal
immune system and mucosal inflammation; in this sense, mucosal mast cells - at
cellular level - and corticotropin releasing factor (CRF) - at molecular level -
seem to play a crucial role. On the other hand, an array of adaptive responses
have been evolved in order to maintain the homeostasis and to ensure the survival
of the individual. In the gut mucosa anti-inflammatory pathways counteract the
deleterious effect of the stressful stimuli on the gastrointestinal homeostasis.
In the present review we discuss the several experimental approaches used to
mimic human stressful events or chronic stress in laboratory animals, the
evidence of stress-induced gastrointestinal inflammation and dysfunction derived
from them, and the involved cellular and molecular mechanisms that are being
discovered during the last years.


PMID: 18537637 [PubMed - indexed for MEDLINE]

a long time now, and have read the Celiac boards for years.

I can't recall finding out the "why" it is higher in some people than others.
It just "is".

If you Google it there are many hits, including the drug company who has a compound in trials.

Here is an interesting Wiki, with illustrations:
http://en.wikipedia.org/wiki/Tight_junction

I think PD along with other CNS neuro problems, may have a connection to gluten intolerance.
Here is the Gluten file:
http://jccglutenfree.googlepages.com/

It is a huge collection of data, including neuro issues and very helpful.
Going gluten free may be very helpful for some people here.