Talk:Blood–brain barrier

Something Important That Is Not Explained In the Article
And which is now inquired about here, up at the top of the discussion, for the sake of attracting attention. Right near the beginning of the article on the blood-brain barrier, it needs to be explained what species of animals have this barrier and which ones do not. I will next be more specific to clarify what I mean by this problem. A. Is the blood-brain barrier only possessed by human beings? B. Is the blood-brain barrier only possessed by the great apes, including human beings? C. Is the blood-brain barrier only possessed by primates? D. Is the blood-brain barrier only possessed by primates, plus the larger and more- intelligent species such as elephants, cattle, horses, canines, felines (cats, lions, etc.), cetaceans (whales, dolpins, etc.), and swine? E. Is the blood-brain barrier only possessed by mammals of all kinds? F. Is the blood-brain barrier possessed by birds? G. Is the blood-brain barrier possessed by reptiles? H. Is the blood-brain barrier possessed by amphibians? I. Is the blood-brain barrier possessed by fish? J. Is the blood-brain barrier possessed by some kinds of invertebrates?

Stating what varieties of creatures have the blood-brain barrier, and which ones don't, is an important issue. As it stands now, this article is rather like one on "The Appendix" that does not mention what species have one and what species do not. I recently read a science-news article that mentioned that there are many different species of mammals that have appendices, but many, many species of mammals that do not. The article was more specific than this, but that is beside the point - to go further than this. The example is made.98.67.164.50 (talk) 15:22, 18 November 2009 (UTC)
 * 2021 and this is still not mentioned. Sad.71.63.160.210 (talk) 01:41, 22 May 2021 (UTC)

Flushing rabies out by opening the BBB
There's research confirming that a rabies infection can be flushed out of the brain by opening the BBB, currently the article erroneously states no attempts have been made to confirm this. I've never edited a wiki article and should be studying something other than wiki tools.. Source: https://www.sciencedaily.com/releases/2007/09/070904164525.htm
 * That is an outdated 2007 lab study, so is unencyclopedic. For the encyclopedia, we need systematic reviews of completed, high-quality clinical trials; see WP:MEDRS as a source quality guide. None of this exists from quality clinical research for a BBB-rabies connection or for any disease where the BBB is purposely "opened" using hyperosmotic or high-pressure carotid infusion, which has dangerous potential consequences for brain homeostasis. It is not an accepted clinical procedure. --Zefr (talk) 13:34, 6 August 2018 (UTC)

Solutes and bacteria
"The blood-brain barrier restricts the diffusion of solutes in the blood (e.g., bacteria)"

Is bacterium a solute? Can it "dissolve" in plasma and extracellular fluid? The definition of solute from the article on Solution is "... a substance dissolved in another substance, known as a solvent."--Mirrordor 03:10, 30 August 2018 (UTC) — Preceding unsigned comment added by Mirrordor (talk • contribs)

Cryptic introduction
In my opinion, the introduction of this article is rather cryptic. It uses a lot of terms that I am not familiar with. Would it be possible to give a more understandable introduction? For example, this scientific article seems to explain the blood brain barrier in a more understandable way in its introduction: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4292164/ NewtonFan (talk) 22:57, 4 January 2019 (UTC)

A Commons file used on this page has been nominated for deletion
The following Wikimedia Commons file used on this page has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 13:07, 20 January 2019 (UTC)
 * Brain Microvessel.tif

Anatomical vs. functional content and sources
The BBB is difficult to study, requiring post-mortem, microscopic examination of capillary structure and presumed function in lab animals, and mainly inferential, semiquantitative biomarker or imaging analysis in humans. From lab animal studies, the anatomical information presented in the article is as reliable and detailed as possible. But this is not the case for implying BBB function and impairment - or as a cause - in some human diseases. Dubiously sourced, misleading content has been removed, as summarized here:
 * drug delivery
 * COVID-19
 * Alzheimer's disease, here and here
 * anxiety and depression
 * neuromyelitis optica
 * MS
 * and numerous others inserted into the article in recent years as speculation based on lab research, such as rabies and epilepsy.

Today, this edit under Clinical significance implying receptor involvement (from lab rodent studies) for purposely breaching the BBB to enable drug delivery is too preliminary and speculative to suggest a true BBB property related to 'Clinical significance'. Other topics in that section, such as brain abscess, de vivo disease, HIV encephalitis, and meningitis are out of date, vague, and misleading in the article, so I am removing them. As this 2018 review explains, the function and clinical relevance of the BBB in humans are poorly studied. The article should reflect this reality rather than presenting conjecture. Zefr (talk) 14:41, 28 September 2020 (UTC)

Water transport thru BBB
I removed the reference to water in the lead because it was identified as a macromolecule. I'm not sure which transport mechanism is used for water, so I just left it out completely. It's a very small molecule, but it's polar. If someone knows whether it is passive or active transport, please add it to the article (with a good source).  Sparkie82 ( t • c ) 02:47, 4 October 2021 (UTC)

Arteriolar and capillary network anatomy is not about the BBB
This quote being inserted into the History section by an IP user is not about the BBB, and is not sourced to a WP:MEDRS or reliable anatomical source. "In his 1702 work De Fibra Motrice, Giorgio Baglivi was the first to discover that when large erythrocytes reach a smaller diameter capillary via micro arterial branching, they have no other option but to return to systemic circulation." i have removed it, but the IP editor is warring and has now reached WP:3RR. Zefr (talk) 17:12, 19 November 2022 (UTC)


 * I read your note here in BBB land and wondered if I might bother you to read my query, "Switch out Lewandowsky" below. I'm a very infrequent contributor and do not want to offend so am happy to take any guidance you might offer :) Joseph stewart (talk) 19:48, 27 February 2023 (UTC)

Switch out Lewandowsky? Or add Stern?
I was reading an article and it asserts that Lewandowsky did not use the term blood brain barrier,

The term “blood-brain barrier” “Blut-Hirnschranke” is often attributed to Lewandowsky, but it does not appear in his papers. The first person to use this term seems to be Stern in the early 1920s.

https://www.frontiersin.org/articles/10.3389/fnins.2014.00404/full. Joseph stewart (talk) 21:55, 8 February 2023 (UTC)


 * I think we ought to update this statement. Perhaps using precisely the phrasing from the reference?  As in, replace the Lewandowsky comment with,
 * The term blood-brain barrier is often attributed to Lewandowsky, but it does not appear in his papers. The first person to use this term seems to be Lina Stern, a Russian scientist who published her work in Russian and French, which may explain the late recognition. In fact, she coined the expression blood-brain barrier in French. Joseph stewart (talk) 19:45, 27 February 2023 (UTC)

Misspelled title/lemma
The lemma contains a dash, specifically an en-dash ("–"), where, I'm pretty sure, a hyphen ("-") is appropriate. Shouldn't it be "Blood-brain barrier" and not "Blood–brain barrier"? Just like e.g. "Turko-Russian war", "east-west relations", "one-two punch" etc. Some big dash fan must've been here! Or am I wrong? Just wanna check in before I go ahead and move the article. Mardil (talk) 10:04, 13 March 2023 (UTC)


 * Agree. WP:DOIT. Zefr (talk) 14:40, 13 March 2023 (UTC)
 * Note from the WP Help Desk: The relevant MOS section is MOS:DASH, which says that in cases like this (where the two terms are symmetric and the first is not a modifier of the second), a long dash should be used rather than a hyphen. Directly addressing this question, it says In article titles, do not use a hyphen (-) as a substitute for an en dash, for example in eye–hand span (since eye does not modify hand). Nonetheless, to aid searching and linking, provide a redirect with hyphens replacing the en dash(es), as in eye-hand span. There is indeed already a redirect from Blood-brain barrier to Blood–brain barrier. Zefr (talk) 18:08, 13 March 2023 (UTC)
 * Thanks for clearing this up! Though I gotta say it strikes me as a weird rule. But a rule is a rule, right? Or is it? I better not check whether it's actually applied in other articles. Mardil (talk) 07:45, 14 March 2023 (UTC)
 * To put it another way, I was unaware of this type of dash usage, which seems to me a bit newfangled and hypercorrective. I'm just reading up on it. I'm glad to hear it's not universally accepted: "Preference for an en dash instead of a hyphen in these coordinate/relationship/connection types of terms is a matter of style, not inherent orthographic "correctness"; both are equally "correct", and each is the preferred style in some style guides. For example, the American Heritage Dictionary of the English Language, the AMA Manual of Style, and Dorland's medical reference works use hyphens, not en dashes, in coordinate terms (such as "blood-brain barrier"), in eponyms (such as "Cheyne-Stokes respiration", "Kaplan-Meier method"), and so on." Mardil (talk) 07:53, 14 March 2023 (UTC)

Blood brain barrier
Deplin is a brain food that has been found to contain a high amount of the protein needed for the blood brain barrier to function properly? Eringeo70 (talk) 08:52, 30 May 2023 (UTC)


 * Deplin redirects to levomefolic acid. From this PubMed search, there are no good sources to indicate deplin itself as a "food" or supplement affects the BBB; folate deficiency is a factor in BBB function. Zefr (talk) 14:57, 30 May 2023 (UTC)