The brain is permeated by a vast network of tiny blood vessels called capillaries- so tiny and thin that blood cells have to pass through in single file. In the brain alone there are enough capillaries that if you laid them all out end to end they would stretch from Tucson to Tijuana.
These capillaries are surrounded by a single layer of cells.
That layer of cells forms a barrier between the capillaries and the cells and fluid of the brain.
These barrier-forming cells are called "endothelial cells". You can think of "endothelial" as a synonym for "lining" or even just "barrier".
When we use the phrase Blood Brain Barrier, (which for obvious reasons we'll refer to as BBB from here on out!), we're talking about all of these endothelial ("barrier") cells collectively.
Function of the BBB
The cell membranes of the BBB contain transport proteins. If the brain is a nightclub, the transport proteins are bouncers. They decide who gets in, and who gets kicked out.
On this website we'll be introducing you to the most important transport proteins- OATP, MDR1, and MDR2.
Don't let all the acronyms intimidate you- read carefully and you'll be fine. If the nightclub/bouncer analogy doesn't work for you, you could also think of them as little vacuum pumps and blowers. An extremely detailed view of their actual mechanisms is beyond current knowledge.
Importance of the BBB
Without the BBB, undesirable molecules could freely diffuse from the capillaries to the fluid that surrounds the brain cells.
These undesirable molecules include:
TOXINS- poisons taken in from the environment.
IONS- that might upset the delicate electrochemical gradients of the cerebral fluid.
ACIDS and BASES- that might upset the cerebral ...
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...aks down the BBB, so the mice infected with GBS lacking this toxin developed less bacterial meningitis than those infected with the normal GBS.
-Doran says: “These findings demonstrate a novel function of the blood-brain barrier, to act as a sentry that detects the threat of a bacterial pathogen and responds by triggering an immune response to clear the infection.
3. Neuwalt- Researches treatment of brain tumors with chemotherapy, hard because of the BBB (natural defense against chemical transport into the brain) introduction of chemicals to the brain by shrinking endothelial cells that make up the BBB with a concentrated sugar solution that creates gaps in the BBB allowing chemicals to enter (called Blood-Brain Barrier Disruption Therapy) project tenfold to a hundredfold more successful than normal chemotherapy and intra-arterial chemotherapy (Neuwalt, 1998)
Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22441230.
The braine has three layers into exterior of the entire brain.1-meninges, 2-dura mater and 3-arachnoid layer and the pia mater.
Its ability to inhibit sodium channels within brain cells thereby protecting the cells from hypoxia (lack of oxygen)
The endothelium is a cell layer that is lined on the interior surface of lymphatic vessels and blood vessels, which are made up of endothelial cells (Dorland, 2012).
Research Updates. University of Rochester Medical Center. November 10, 2008. National Institutes of Health. February 6, 2009. < http://www.urmc.rochester.edu/neurology/nih-registry/research/index.cfm>.
The blood-brain barrier (BBB) is a highly specialized endothelial barrier which separates components of the circulating blood from neurons.[6] The BBB acts as the interface between the vascular system and the brain that restricts and regulates the exchange of substances.[7] The blood- brain barrier is responsible for the maintaining of homeostasis of the brain through regulating the chemical environment, the entry of xenobiotic and the immune cell transport.[8, 9] The concentration of water, ions, amino acids, hormones and neurotransmitters in the blood undergo fluctuations. If those fluctuations were allowed to occur in the brain it would lead to local disruption of signal propagation and uncontrolled neural activity.[8, 10] Interruption of cerebral blood flow would result in neuronal death.[11]
Culter, Mary Ann, Joanne Dombrowski, Michael Doughtery, Paula Henderson, and Laura McNicholas. “The brain: understanding nuerobiology. The brain-lesson1-What does this part of the brain do?” NIH publication, Mar.20120.21.Apr.2014.
Brain Aneurysms What is a brain aneurysm? One could define a brain aneurysm as a bulging, weak area in the wall of an artery that supplies blood to the brain. Over time, weak areas in the walls bulge out, causing the blood vessel walls to become weaker as the aneurysm grows (Simon). In most human beings, a brain aneurysm can go undetected for years, even possibly one's entire life. Some people however are not so lucky, in some instances, the aneurysm can rupture or explode, causing a hemorrhagic stroke, which is known as the type of stroke that causes bleeding in the brain.
It is caused by clot that blocks blood vessels from supplying blood to the brain through cerebrovascular events. If there is no blood in the brain, then there is no oxygen or nutrients because it is blood that supplies it to the brain. This can cause permanent brain damage which can cause inflammation. Fasting has there been known to be effective and efficient against stroke because it increases cognitive functioning and health of the brain. In addition, fasting has been known to increase neuro-protective proteins and reduction in inflammatory substance known as cytokines. This is critical reducing the chances of damaging the brain that can cause
To achieve this aim, this report will firstly talk about the cerebrovascular system with its structure and functions. The main body of this report will look at causes, symptoms, diagnosis, treatments and prevention of stroke. 2. What is the difference between a.. Cerebrovascular system a) Overview of the cerebrovascular system b) Normal function 3.
The brain consists of both neurons and glia cells. The neurons, which are cells housed in a cell body called a Soma, have branches which extend from them, referred to as dendrites. From these dendrites extend axons which send and receive impulses, ending at junction points called synapses. It is at these synapse points that the transfer of information takes place.
Innate system critical main defense is the cellular component; there are several kinds of cells involved in the process. One of the crucial cells is the macrophage. ...
This fluid is what the brain literally floats in. A third protective measure taken by the brain is called the blood brain barrier. This barrier consists of a network of unique capillaries. These capillaries are filters for harmful chemicals carried by the blood, but do allow oxygen, water and glucose to enter the brain.
The dermal tissue system consist of epidermis and periderm whose cells contain protoplasm and nucleus without intercellular spaces. The dermal tissue system is theprotective outer layer for the whole part of plant. It acts like human skin which forms the first line of defence against physical damage and pathogen.A single tissue called epidermis, is a layer of tightly packed cell usually found in non-woody plant or herbaceous plants. The epidermis forms a protective cover in plant organs like stem, flower, fruits and leaves. Epidermis possesses numerous minute openings called stomata, thesmall gated pores that are formed bythe guard cells and their subsidiary cellswhose main function is the exchange of gases between the
It’s a boundary that separates the inside from the outside of a cell. The cell membrane is structured by a blend of protein and lipids. It controls the motion of substances from coming in and out of a cell. Making sure the particles stay inside so nothing can get it and damage it. Ironically it isn’t a solid structure, it’s a container made of smaller molecules.