|This article is of interest to the following WikiProjects:|
|Epithelium has been listed as a level-4 vital article in Science. If you can improve it, please do. This article has been rated as C-Class.|
- 1 Epithelial Genetics ?
- 2 "Structure" and "Classification" sections redundant?
- 3 Swapping columnar for cuboidal- thoughts
- 4 Adding microscopice photos for content 1.1
- 5 question about basement membrane
- 6 epi- vs. endothelium
- 7 "non-keratinised stratified squamous" issue
- 8 Shape/Squamous desc
- 9 Lining versus glandular epithelium
- 10 general characters of epithelial tissue
- 11 Misplaced link for lining of heart
- 12 what structures?
- 13 Vascular or not?
Epithelial Genetics ?
"Structure" and "Classification" sections redundant?
(Topic added 02/10/09)
The two sections are confusingly similar and overlap in a lot of places. They should be consolidated into one section. --(Anon i.e. don't have an account, 2/10/09)
Swapping columnar for cuboidal- thoughts
I have replaced the simple columnar of the prox. and dist. convoluted tubules with simple cuboidal. I have done this because all textbooks I have checked refute the original statement. In particular, I referenced the Colour Textbook of Histology, Elsevier, 2007 pp458. I think this is a minor change & one well supported by evidence. Welcome to other opinions. —Preceding unsigned comment added by 188.8.131.52 (talk) 04:30, 13 February 2009 (UTC)
Adding microscopice photos for content 1.1
(Discussion topic added on 13/10/08)
shall we add some photos to give clearer ideas of the followings?
here may be a website that helps: 
question about basement membrane
current version: Epithelial cells sit on a basal lamina (formerly called a basement membrane).
I agree that it is probably best to use the term "basal lamina", but "basement membrane" is still used more frequently by biologists. Maybe it would be better to say that historically the term "basement membrane" became popular, but cell biologists are trying to restrict use of the term "membrane" to structures that contain one or more lipid bilayer membranes.184.108.40.206 16:46, 4 Dec 2004 (UTC)
- I've seen references of "basement membrane" used elsewhere besides epithelia and I don't want to suggest that everything that was/is called a basement membrane is now called a basal lamina. If you visit http://herkules.oulu.fi/isbn9514272374/html/x158.html you'll see that they refer to basement membranes "surrounding individual muscle fibers, blood vessels, Schwann’s cells and spindle capsule cells". I don't think it would be correct to say the basal lamina of muscle, Schwann & capsule cells, but more specifically endomysium and endoneurium. (Basal lamina would be correct for blood vessels though, since the cells are epithelial.) I understand that "basement membrane" might still be popular but since the article deals with histology, accepted terms in histology should be used. IMO, it would be like changing "sarcolemma" to the better known "cell membrane" in any article dealing with muscle; it's not necessarily wrong, but the technical accuracy of the article shouldn't be compromised because people in a different field call it something else.
- Maybe a stub for basement membrane is warranted?--jag123 19:03, 4 Dec 2004 (UTC)
The histology book I have (Michael H. Ross et al 2003) says on page 107, "The terms basement membrane and basal lamina are used inconsistently in the literature. Some authors use basement membrane when referring to both light and electron microscopic images. Others dispense with the term basement membrane altogether and use basal lamina in both light and electron microscopy. Because the term basement membrane originated with light microscopy it is used in this book only in the context of light microscopic descriptions and only in relation to epithelia. The electron microscopic term basal lamina is reserved for the ultrastructural content to denote the layer present at the interface of connective tissue with epithelial cells. The term external lamina is used to identify this same layer when it forms a peripheral cellular investment as in muscle cells and peripheral supporting cells." --dsws 01:58, 13 July 2005 (UTC)
Hey... why is there an eyeball picture???
please add the meaning of tissues
epi- vs. endothelium
Just a quick note to say that the opening sentence strikes me as rather odd, since it conflates epithelium with endothelium. I didn't edit it, however, since I'm not a biologist. Nevertheless, since the prefix of one glosses as "inside" (as in endoskeleton, the sort of skeleton us humans have), while the other glosses as "above" or "over" (as in the epicenter of an earthquake, meaning the ground-level center located above the underground, actual, center of techtonic movement), it seems wrong to me. And, since people use this encyclopedia for school-related research, it seems worth a mention. Someone with the relevant expertise ought to remedy this. Buck 04:17, 23 January 2006 (UTC)
- Both the ectoderm and the endoderm develop into epithelium. Endothelium is of mesenchymal origin. I will have a look. JFW | T@lk 08:22, 23 January 2006 (UTC)
- It was utterly wrong. Epithelium of the viscera is still epithelium! Endothelium is completely different. JFW | T@lk 08:27, 23 January 2006 (UTC)
- Endothelium must fall into one of the four tissue types: muscle, neural, connective, epithelial. So is it not epithelial tissue?--Drewlew 05:14, 12 April 2006 (UTC)
- The terms "epithelium" and "endothelium" are counterintuitive, I agree. However, the article is correct -- there is no conflation of terms. The confusion arises from the difficulties of anatomical orientation at various levels in a convoluted body plan. Endothelium is "endo" because it's on the "inner" surface of the blood vessel or heart chamber, i.e. it forms the boundary with the lumen of the structure. So in terms of gross body structure, this is the "deepest" you can get. But histologically, it's still epithelium based on its characteristics. Anyway, if it helps you, at the level of the tissue layers it's more natural to think of the layer with a free surface as being the most superficial, i.e. "epi". --Mark Lundquist 15:38, 16 August 2006 (UTC)
"non-keratinised stratified squamous" issue
What do you mean when you say "non-keratinised stratified squamous" epithelium is found in human oesophagus(oral mucosa)? Are you strictly talking about the area of the mouth or are you including the actual esophagus as well? Another thing is that normal esophageal squamous cells do not produce mucus, so that would be a contradictory if that was what was referred to. However, the presence of non-keratinised cells would be more interesting because it seems that esophageal cells are only keratinised. Can you tell me where these no-keratinised cells exactly are? If possible, could you maybe forward these questions to a different specialist if you are not sure? Thank you.
I've reworded the desc for Squamous cells slightly. The original didn't read quite right:
- The one-cell layer of simple squamous epithelium that forms the alveoli of the respiratory membrane, and the endothelium of capillaries, and is a minimal barrier to diffusion.
Wasn't sure if it meant "A one-cell layer...forms...capillaries, and is a minimal barrier..." or "The one-cell layer...that forms...capillaries, is a minimal barrier...", I went with the former.
Zarius 07:40, 16 March 2007 (UTC)
Lining versus glandular epithelium
I think this article needs a significant work-over because it defines epithelial tissue in terms of its omnipresent appearance as a thin layer of cells either one cell thick (simple) or several layers thick (stratified). This does not provide a definition which can encompass glandular epithelium.
general characters of epithelial tissue
I have added general characters of epithelial tissue that is present in most of histology books and it is essential information for users . —Preceding unsigned comment added by Midozx (talk • contribs) 17:42, 9 December 2009 (UTC)
I think the link to mesothelium is misplaced. The lining of the heart is called the endocardium and is composed of endothelial cells similar to those lining the arteries. The mesothelium, as it's Wiki page says, forms the lining of body cavities like the pleura, the peritoneum and the pericardium. The last of these is near the heart, but not in the heart. Mehrenberg (talk) 11:57, 11 February 2010 (UTC)
Vascular or not?
This sentence contradicts the rest of the article. Please fix it. "Exocrine and endocrine epithelial cells are highly vascular." — Preceding unsigned comment added by Burressd (talk • contribs) 23:57, 29 December 2012 (UTC)