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December 15[edit]

Biology -- corrections[edit]

I am not a biologist but have noticed two cases of evident inconsistency in pages related to the renal system. There is a portal for such things but I do not see how to pass my queries to it. I would be grateful if you would pass these points to the people responsible.

1. The following page links "Ludwig theory" to "Ludwig von Bertalanffy". I think this is a mistake -- from what I can see von Bertalanffy had nothing to do with the study of renal systems. https://en.wikipedia.org/wiki/Bowman%E2%80%93Heidenhain_hypothesis

2. The following page states seems to include a discrepancy between two estimates of filtration rate: "approximately 180 litres of filtrate per day", and (in next sentence) a "normal range" of "800 to 2,000 milliliters per day". The first quantity seems very large and I think it should be corrected to "1,800 milliliters". https://en.wikipedia.org/wiki/Kidney M E T Horn (talk) 04:19, 15 December 2023 (UTC)[reply]

1. The "Ludwig" of the theory is German physician and physiologist Carl Ludwig (1816–1895). Quoting the abstract and the final text section of a paper discussing the issue:^[1]

Marcello Malpighi discovered the glomerulus that bears his name in the 17th century, but it was not until the middle of the 19th century, in 1842, that William Bowman in London published his studies of the histological structure of the glomerulus and proposed that urine formation begins with glomerular secretion. At nearly the same time in Marburg, Carl Ludwig, unaware of Bowman’s findings, proposed that urine formation begins with glomerular filtration followed by tubule reabsorption. The controversy lasted 80 yr.
...
The widespread advances in understanding urine formation were based on the decisive results of the experiments by Joseph Wearn and Alfred N. Richards in 1924 that resolved the controversy in favor of the filtration reabsorption theory of Carl Ludwig and launched the modern era of renal physiology.

Based on this article, it seems to me that the wording "This theory was later merged with ..." is incorrect, and should be, "This theory was later replaced by ...". --Lambiam 10:36, 15 December 2023 (UTC)[reply]

2. The cited source states: "Approximately 180 L/day of glomerular filtrate is generated in an average adult human, the majority of this is reabsorbed by the highly water-permeable proximal tubules and descending thin limbs of Henle's loop." [my emphasis by underlining; --L.] Other sources state the same estimate; for example, ""Thus, in a 24 h period, as much as 180 L/day of plasma is filtered at the glomerulus. In other words, in one day kidneys filter an amount of fluid equal to 4 times the total body water."^[2] The other figure, 800 to 2,000 milliliters per day, is the urine production – the fraction that is not reabsorbed.

Feel free to edit the article so as to make clear to the unaware reader that most of this enormous amount is reabsorbed. --Lambiam 11:05, 15 December 2023 (UTC)[reply]

References

^ Jamison, Rex L. (December 2014). "Resolving an 80-yr-old controversy: the beginning of the modern era of renal physiology". Advances in Physiology Education. 38 (3): 286–295. doi:10.1152/advan.00105.2014.
^ Indu Khurana; Arushi Khurana (2015). Textbook of Medical Physiology (2 ed.). Elsevier Health Sciences. p. 491. ISBN 978-81-312-4254-4.

[1] Jamison, Rex L. (December 2014). "Resolving an 80-yr-old controversy: the beginning of the modern era of renal physiology". Advances in Physiology Education. 38 (3): 286–295. doi:10.1152/advan.00105.2014.

[2] Indu Khurana; Arushi Khurana (2015). Textbook of Medical Physiology (2 ed.). Elsevier Health Sciences. p. 491. ISBN 978-81-312-4254-4.

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