I read post #27 twice before replying, because I had assumed the opposite.
The most useful reply I ever got about reading a rodent study was a request to state my units. It sounds like pedantry and it has saved me twice.
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Compounds · Secretagogues & GH axis · continued
Reading a rodent study on a secretagogue without over-extrapolating posts 31–55
This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.
r.bakken, post #25: The version of reading a rodent study that I was taught turned out to be a teaching simplification. Useful, and not true in the way I had assumed it was. Go to post
Since reading a rodent study keeps coming up, it should probably be a maintained page rather than a recurring thread. I am happy to draft it if someone with more direct experience will review it.
Collapsed as off-topic by two members at trust level 3 or above
Storage: these are lyophilised short peptides and are generally reasonably stable dry and considerably less so in solution. Reconstituting only what will be used within the period the supplier's own data covers is the conservative approach.
The step people skip is the one I have spelled out.
n.achebe, post #21: The number people quote for reading a rodent study is a central estimate presented without its interval, and the interval is wide enough that the estimate is nearly uninformative on its own. Go to post
On reading a rodent study I would separate what is worth knowing from what is worth acting on. The first list is long and the second is short, and conflating them is how threads get heated.
c.inglethorpe, post #9: Post #8 is right about the mechanism and I think understates the practical bit. Evidence quality in the secretagogue literature is honestly weaker than in the incretin literature. Large randomised controlled trials are rare. Most evidence is mechanistic or from small studies. This is why this subcategory has higher sourcing standards… Go to post
What a well-designed human trial of a secretagogue would look like: randomised, placebo-controlled, adequate sample size, IGF-1 as primary outcome, muscle and strength as secondary outcomes, adequate follow-up duration. Very few secretagogue trials meet that description.
e.kimani, post #1: Posting this under the heading it deserves: Reading a rodent study on a secretagogue without over-extrapolating Everything below is what sits behind that. Reading a rodent study, and specifically the version of it that the documentation does not cover. The maintained page handles the general case well and stops exactly where my question… Go to post
Genuine question rather than a rhetorical one: has anyone here actually observed reading a rodent study, as opposed to read about it? The thread is long and I cannot tell.
Evidence quality in the secretagogue literature is honestly weaker than in the incretin literature. Large randomised controlled trials are rare. Most evidence is mechanistic or from small studies. This is why this subcategory has higher sourcing standards than most.
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a.batista, post #37: On reading a rodent study I would separate what is worth knowing from what is worth acting on. The first list is long and the second is short, and conflating them is how threads get heated. Go to post
I read post #42 twice before replying, because I had assumed the opposite.
What I want from this reading a rodent study thread is the list of things that would need to be true for the claim to hold. If we can write that list, we can check it.
d.tamm, post #35: A purity figure without a method for a short peptide is nearly uninterpretable, because short peptides can be run on gradients that resolve almost nothing and still produce a clean-looking trace. I would rather say I do not know than round it up to an answer. Go to post
Narrowing post #44, because the general version has more than one answer.
CJC-1295 exists in two forms in circulation — with and without the drug affinity complex — and they have very different half-lives. Product descriptions frequently do not say which, and the difference is not cosmetic.
I have left out the parts I could not verify.
a.asante, post #46: On analysis: these are short peptides and generally straightforward chromatographically, which means a poor purity result is more likely to reflect the synthesis than the method. Go to post
Everything in post #46 holds. The case it does not cover is the one I have.
The thing about reading a rodent study that took me longest to accept is that a plausible mechanism is not evidence of an effect. It is a reason to look, not a result.
Where I part company with post #46, and it is a narrow parting.
Effects reported at the level of appetite are the most consistently described and the most mechanistically direct for the ghrelin-receptor compounds, which is not what most people are taking them for.
This has been discussed before and I could not find the thread, so, again.
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CJC-1295 with and without DAC: the version with a drug affinity complex binds albumin covalently and persists for days. The version without it does not persist. Supplier labelling frequently does not distinguish them clearly, so confirming which you have is important.
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I changed my mind about reading a rodent study after someone here asked me for the source and I could not produce one. That is worth saying out loud because it is the ordinary way it happens.
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m.stephanopoulos, post #32: Since reading a rodent study keeps coming up, it should probably be a maintained page rather than a recurring thread. I am happy to draft it if someone with more direct experience will review it. Go to post
Post #49 describes the usual case. This is about the unusual one.
Speaking only to reading a rodent study as I have actually seen it, rather than as it is usually described: the effect is real, it is smaller than the thread suggests, and the variance between people is larger than the effect.
A mass result for a short peptide is more discriminating than for a long one, because a single residue difference is a larger proportion of the total. That makes identity confirmation genuinely useful here.
Nothing above should be read as advice about what anyone else should do.
26 likes 10mo
This topic was referenced in
- About the Secretagogues & GH axis categoryCompounds › Secretagogues & GH axis · 10 replies
This topic was closed 60 days after the last reply. Closing is automatic for quiet topics so that a settled answer does not collect new questions underneath it. If you have a follow-up, open a new topic and link back to this one — that keeps both readable and gives your question its own title.
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