Talk:Thoracic splanchnic nerves

"Smallest splanchnic nerve" listed at Redirects for discussion

An editor has asked for a discussion to address the redirect Smallest splanchnic nerve. Please participate in the redirect discussion if you wish to do so. Steel1943 (talk) 22:07, 20 September 2019 (UTC)

Hindgut

@Bibeyjj: You added in this edit ([1]) that "the least splanchnic nerve modulates the activity of the enteric nervous system of the hindgut". Do you have a source for that? RcAlex36 (talk) 08:39, 30 October 2021 (UTC)

Hi RcAlex36! There is no reference for any of the nerves at the moment. The best I can find is this reference, which indicates that each thoracic splanchnic nerve supplies specific ganglia that then supply each part of the ENS (I will add this now, with appropriate rephrasing). In terms of other information, this reference says that the greater splanchnic nerve controls blood volume. This reference mentions sensory afferents, but not efferents (modulating). This reference mentions the ganglia that each splanchnic nerve supplies. I hope these are useful! Bibeyjj (talk) 09:29, 30 October 2021 (UTC)

@Bibeyjj: What you have put in the edit was wrong. The least splanchnic nerve supplies sympathetic innervation to the kidneys and not the hindgut, and sympathetic innervation to the hindgut is supplied by the lumbar splanchnic nerves instead. Please double-check with sources when you edit anatomy-related entries—I've caught you making a mistake in this edit ([2]) at internal spermatic fascia which went unnoticed for months. RcAlex36 (talk) 09:37, 30 October 2021 (UTC)

Hi RcAlex36! Unfortunately, your statement about the least splanchnic nerve (which you provided no reference for) only supplies the kidney is incorrect, as it supplies both the kidney and the hindgut ([3]). I included this reference in my last reply.

Regarding your query about the internal spermatic fascia, the transversalis fascia is a continuation downward of the aponeurosis from the transverse abdominal muscle ([4]), as I stated originally. To say that the internal spermatic fascia is derived from the transversalis fascia is also correct, so I will not undo your edit.

If you have any more queries, please do say. Thanks! Bibeyjj (talk) 10:24, 30 October 2021 (UTC)

@Bibeyjj: As far as I am aware, most recent standard textbooks do not claim that the least splanchnic nerve synapses with the inferior mesenteric ganglion.

• Moore's Essential Clinical Anatomy 6th Edition writes, "The renal plexus is supplied by fibers from the abdominopelvic (especially the least) splanchnic nerves", and "the suprarenal glands have a rich nerve supply from the celiac plexus and abdominopelvic (greater, lesser, and least) splanchnic nerves". The least splanchnic nerve may also contribute to the superior mesenteric plexus according to the book.
• Gray's Anatomy for Students 4th edition writes, "The least splanchnic nerve, when present, arises from the twelfth thoracic ganglion and travels to the renal plexus."
• Gray's Anatomy 41st edition section "Least Splanchnic nerve" writes, "On each side, the least splanchnic nerve is derived from the medial, visceral branches of the eleventh and/or twelfth thoracic ganglia. It enters the abdomen medial to the sympathetic chain under the medial arcuate ligament of the diaphragm and runs inferiorly to join the renal plexus. The trunk of the nerve enters the aorticorenal ganglion and may give branches to the lateral aspect of the coeliac ganglion. It is sometimes part of the lesser splanchnic nerve, when it forms a twig that enters the renal plexus just below the aorticorenal ganglion."

I assume that these books represent the current consensus on the understanding of the least splanchnic nerve, or the typical situation in most people. RcAlex36 (talk) 10:58, 30 October 2021 (UTC)

Hi RcAlex36! Thanks for letting me know, and based on these references I completely agree that the consensus is that, at most, the least splanchnic nerve supplies the kidney and possibly the superior mesenteric ganglion but not the inferior mesenteric ganglion. I will add a Gray's reference to the article. Sorry for not seeing this consensus earlier. Bibeyjj (talk) 11:07, 30 October 2021 (UTC)