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Get a better picture, it looks like a fifth grader drew it in paint.

Here's a picture that I think would be appropriate, but I don't know how to replace it: EerieNight 10:03, 4 September 2007 (UTC)

See WP:IMAGE, it would have to be fair use, and uploaded to wikipedia or WP:COMMONS. At that point the picture could be replaced. You can't just pull images off the net and put them up unfortunately. WLU 02:26, 9 September 2007 (UTC)

why is there no image at all now? —Preceding unsigned comment added by (talk) 23:15, 15 March 2011 (UTC)

link to Excitation-contraction coupling when talking about muscle contraction at the end of 'sarcoplasmic reticulum' - this would have saved a lot of my research time had it been included.

Beta-adrenoceptors - removed[edit]

I've done a fair bit of tidying up of this article tonight. I felt that the section on Beta-adrenoceptors was disproportionately detailed and drastically cut it down. If anyone feels it should stay then the text is here.

Not only that but beta adrenoceptors are also highly concentrated here.[1] Beta adrenoceptors are receptors that are activated by adrenaline. Adrenaline is a hormone released from the adrenal gland, as part of the bodies fight or flight response. When adrenaline binds to the beta adrenoceptor, it activates it. This activation, simulates a protein called a Gs-protein, which initiates a series of reactions (known as the cyclic AMP pathway), leading to the production of Protein Kinase A (PKA). Protein Kinase A has the ability to add a phosphate to its target. In this instance one of PKAs targets is the RyR. The RyR is bound to a protein called FKBP (FK-506 binding protein), which prevents the RyR from opening. However, when the RyR becomes phosphorylated, by PKA, the FKBP unbinds, meaning that the RyR is more sensitive to stimulation. This means that there is an increased release of calcium from the SR.[2]

PeaBrainC (talk) 04:40, 18 November 2017 (UTC)

@PeaBrainC totally support. This information should be on the relevant article, not here. --Tom (LT) (talk) 06:38, 26 November 2017 (UTC)

GA Review[edit]

This review is transcluded from Talk:T-tubule/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Tom (LT) (talk · contribs) 06:53, 26 November 2017 (UTC)

Hi PeaBrainC, I'll take up this review. Loving your work so far around here. Good articles are reviewed against 6 criteria (WP:GA?) and I will use these to review the article. I'll first spend a few days familiarising myself with the article and then post my review. --Tom (LT) (talk) 06:53, 26 November 2017 (UTC)
I've made 2-3 small edits to the article. --Tom (LT) (talk) 06:55, 26 November 2017 (UTC)
Rate Attribute Review Comment
1. Well written:
1a. the prose is clear, concise, and understandable to an appropriately broad audience; spelling and grammar are correct. Well-written and concise
1b. it complies with the manual of style guidelines for lead sections, layout, words to watch, fiction, and list incorporation.
2. Verifiable with no original research:
2a. it contains a list of all references (sources of information), presented in accordance with the layout style guideline. Some parts lacking citations resolved
2b. all inline citations are from reliable sources, including those for direct quotations, statistics, published opinion, counter-intuitive or controversial statements that are challenged or likely to be challenged, and contentious material relating to living persons—science-based articles should follow the scientific citation guidelines.
2c. it contains no original research.
2d. it contains no copyright violations nor plagiarism. No violations identified; only the usual suspects mirroring WP content.
3. Broad in its coverage:
3a. it addresses the main aspects of the topic. See comments resolved
3b. it stays focused on the topic without going into unnecessary detail (see summary style). Well-focused
4. Neutral: it represents viewpoints fairly and without editorial bias, giving due weight to each.
5. Stable: it does not change significantly from day to day because of an ongoing edit war or content dispute.
6. Illustrated, if possible, by media such as images, video, or audio:
6a. media are tagged with their copyright statuses, and valid fair use rationales are provided for non-free content. Great selection of images; nil issues
6b. media are relevant to the topic, and have suitable captions.
7. Overall assessment.


A really well-written article, I only have a few comments:

  • In general very well-written; images are great and very helpful, references are excellent
  • No copyright / image issues identified
  • Several sentences lack references:
    • "T-tubules within the heart are closely associated with a region of the sarcoplasmic reticulum known as terminal cisternae. The association of the T-tubule with a terminal cistern is referred to as a dyad." : Done
    • "The sodium-calcium exchanger passively removes one Ca2+ ion from the cell in exchange for three Na+ ions. As a passive process it can therefore allow calcium to flow into or out of the cell depending on the combination of the relative concentrations of these ions and the voltage across the cell membrane (the electrochemical gradient). The Ca2+ATPase removes calcium from the cell actively, using energy derived from adenosine triphosphate (ATP)." : Done
    • "(for skeletal and cardiac muscle respectively) can be added to the extracellular solution that surrounds the cells. These osmotically active agents cannot cross the cell membrane, and their addition to the extracellular solution causes the cells to shrink. When these agents are withdrawn, the cells rapidly expand and return to their normal size. The rapid expansion causes T-tubules to detach from the surface membrane." : Done
  • One main area missing (per WP:MEDMOS#Anatomy) is a short 'history' section relating to T-tubules : DonePeaBrainC (talk) 19:29, 5 December 2017 (UTC)
  • It isn't a requirement for this review, but I think that to improve the readability of this article for a general audience, given its excellent subject matter, several changes could be made (WP:ANATSIMPLIFY).
    • "extracellular/intracellular" -> "fluid outside of the cell; fluid inside the cell"
    • "dyad" -> "pair"
    • cardiomyocytes -> heart muscle cells
    • spelling out SR -> sarcoplasmic reticulum
    • Ca2+ -> "calcium"
 Done Good suggestions re: wording, I have tried to accomodate most of these. I have left "dyad" beacuse as a specific technical term it doesn't translate perfectly as pair. PeaBrainC (talk) 20:45, 1 December 2017 (UTC)

Looking forward to your response, happy to discuss any of the points above, --Tom (LT) (talk) 07:46, 28 November 2017 (UTC)

Thanks Tom(LT) - I'll make these amendments ASAP. May take me a few days to research the history section.PeaBrainC (talk) 11:58, 1 December 2017 (UTC)

Hi Tom (LT) - I hope I've addressed all your comments - what are your thoughts? -- PeaBrainC (talk) 19:29, 5 December 2017 (UTC)
@PeaBrainC looks great, thanks for your responses! Promoted, and well done! --Tom (LT) (talk) 10:09, 7 December 2017 (UTC)


Thanks Tom (LT) - looking forward to hear your thoughts. My first time nominating a GA so there's plenty for me to learn! PeaBrainC (talk) 14:53, 26 November 2017 (UTC)


  1. ^ Laflamme, M. A.; Becker, P. L. (1999-11-01). "G(s) and adenylyl cyclase in transverse tubules of heart: implications for cAMP-dependent signaling". The American Journal of Physiology. 277 (5 Pt 2): H1841–1848. ISSN 0002-9513. PMID 10564138.
  2. ^ Bers, Donald M. (2006-05-15). "Cardiac ryanodine receptor phosphorylation: target sites and functional consequences". Biochemical Journal. 396 (Pt 1): e1. doi:10.1042/BJ20060377. ISSN 0264-6021. PMC 1450001. PMID 16626281.

Where (do they occur)?[edit]

This is part of the very first sentence: of skeletal and both atrial and ventricular cardiac muscle cells. It is obviously a very important fact about the T-tubule, so it is good that it is stated here (the types of cells where they occur). Since it is so important, it should also be stated clearly in the main text. There is a general rule that all facts that are in the intro should also be in the main body of the article. Although it is assumed here and there in the article, I cannot find it explicitly stated.

Also, I think the first sentence should be less difficult to read. Suggest a change to of skeletal cells and cardiac muscle cells. The intro is to be a summary. The details of atrial and ventricular can be spelled out where the distribution is described in the body of the article. --Ettrig (talk) 10:19, 1 December 2017 (UTC)

 Done PeaBrainC (talk) 20:31, 1 December 2017 (UTC)


Concerns with Detubulation section[edit]

The statement "These osmotically active agents cannot cross the cell membrane, and their addition to the extracellular solution causes the cells to shrink." is incorrect. Formamide is permeable to the cell membrane and will induce transient cell volume changes. Therefore, the statement should be changed to "Addition of these osmotically active agents cause the cells to shrink." The statement "The rapid expansion causes T-tubules to detach from the surface membrane.[17]" cites a paper that directly contradicts the statement. Reference 17 demonstrates that cell shrinking, not cell expansion, is responsible for detubulation. The notion that cell expansion causes t-tubules to detach from the surface membrane comes from a 1999 paper by Kawai et al (PMID: 10444485) although the exact mechanism of detubulation is still unclear. — Preceding unsigned comment added by (talk) 23:05, 13 July 2019 (UTC)

Thanks for spotting this. Reference 17 refers to the use of hypotonic saline, causing expansion followed by subsequent shrinkage rather than the reverse seen when formamide is used. I have rewritten the text to make it clearer and cited the Kawai paper. Do you think it reads better now? PeaBrainC (talk) 06:58, 21 July 2019 (UTC)