TRH Thyrotropin (Protirelin) (25mg)

(11 customer reviews)


TRH Thyrotropin (Protirelin) peptides are Synthesized and Lyophilized in the USA.

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TRH Thyrotropin (Protirelin) Peptide

Thyrotropin Releasing Hormone (TRH), often called Protirelin, is a small peptide hormone synthesized in the hypothalamus. It was developed by researchers with the intention to stimulate the release of both thyroid-stimulating hormones and prolactin from the anterior pituitary. TRH has been employed in the study anterior pituitary gland function in research models of thyroid disorders. TRH may exhibit potential roles in TREK-1 channel, in the regulation of cell aging, arousal, feeding behaviors, autonomic regulation, and fighting free radical damage.


OTHER KNOWN TITLES: Protirelin, Thyroliberin, Lopremone, Relefact


MOLECULAR WEIGHT: 362.39 g/mol


TRH Thyrotropin (Protirelin) Research

TRH Thyrotropin (Protirelin) and Depression
The thyrotropin-releasing hormone has been referenced in numerous depression-related studies. In an early study, researchers introduced TRH Thyrotropin (Protirelin) directly into the spines of research models. The peptide reported a 50% or more reduction in depressive symptoms compared to controls.[1] The scientists report that “Administration of protirelin… induced a rapid improvement … supporting the hypothesis that thyrotropin-releasing hormone could be a positive modulator of mood.” Researchers have speculated that the specific action of TRH Thyrotropin (Protirelin) in depression may be related to an organism’s emotional state.[2] Researchers sought to explore other methods of introducing TRH Thyrotropin (Protirelin) to research models. The speculated that the peptide may not be able to cross the blood brain barrier (BBB), which helped to narrow their research focus. They found over the course of their studies that exposure during nocturnal sleep appeared to fit better with the natural circadian cycling of TRH. In the study, the percent of those research models given TRH exhibited a 50% or greater reduction in symptoms of depression, which is in keeping with related study findings.[3]

TRH Thyrotropin (Protirelin) and Motor Memory
Motor memory, also called muscle memory, refers to a form of procedural memory that develops through doing a specific motor task repeatedly. Research in mice without the gene for TRH Thyrotropin (Protirelin) have seemed to be slower to learn specific motor tasks, but that learning speed might be increased, researchers speculated, under TRH influence. These findings lended support to an existing research hypothesis that TRH Thyrotropin (Protirelin) may be active in the cerebellum and may play a role in facilitating motor learning. Knockout mice exposed to TRH were observed to learn faster after four trials than unexposed mice.[4] This study suggests the peptide’s potential to improve rates of motor learning. TRH and TRH analogs have been suggested to decrease ataxia in cerebellar degenerative disease models. They have been speculated to do so via their potential impact on motor learning.

TRH Thyrotropin (Protirelin) and Opioids
Research studies into the impacts of opioid exposure examined the effects of THR Thyrotropin peptide, and researchers suggested it may increase breathing rates in a concentration-dependent manner possibly without influencing pain control.[5] In a study of induced-overdose, the peptide appeared to have prevented death in all experimental animal models. This finding was reported alongside a secondary group given Narcan and a control group. The two substances (TRH and Narcan) are speculated to have different mechanisms of action, extending their potential to act in a synergistic manner.

TRH Thyrotropin (Protirelin) and Hypovolemic Shock
Taltirelin, speculated to be a more metabolically stable version of TRH, with a longer half-life, has been tested in the context of acute hemorrhagic shock in rat research models. Preliminary results suggest that Taltirelin might have improved the mean arterial blood pressure and respiratory rate, similar to existing compounds for acute blood loss. In the study, Taltirelin appeared to improve blood pH and may have prevented a decrease in arterial oxygen saturation, making it a potential candidate in research studies related to blood loss and hypovolemic shock.[6]

TRH Thyrotropin (Protirelin) and Disease Development
Changes in TRH levels have been associated with thyroid disease. Researchers have observed that changes in TRH and other thyroid hormones appear to occur in various non-thyroid cases. Research in rats has suggested that specific neurons in the brain may be responsible for this phenomenon, with researchers positing that they lose the ability to produce TRH Thyrotropin (Protirelin) and respond to feedback mechanisms.[7] There is curiosity within the scientific community as to whether TRH supplementation may reduce the severity of non-thyroidal illness in some instances, but research in this area is fledgling.

TRH Thyrotropin (Protirelin) and Cell Aging
Research in mice has suggested that TRH may potentially exert protective characteristics in certain organs against oxidative damage and cell aging. TRH Thyrotropin (Protirelin) appears to reduce the building up of amyloid plaque in the kidneys, a common projected cause of reduced kidney function. Similar impacts were observed over the course of research in the testes of aging male mice. Amyloid plaques are often associated with Alzheimer’s disease (AD), and researchers have been interested in the potential of TRH to potentially mitigate amyloid buildup in the brain the same way that it has been hypothesized to do in the kidneys. Preliminary studies in mice have yielded unclear results.[8] The scientists reported that “This study suggests that [high-concentration] TRH … is neurobehaviorally active.” Research suggests that TRH levels drop in the hippocampus of research models of Alzheimer’s disease, suggesting supplementation might serve a supportive purpose provided TRH has no impact on amyloid buildup in the brain.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.



  1. Marangell LB, George MS, Callahan AM, Ketter TA, Pazzaglia PJ, L’Herrou TA, Leverich GS, Post RM. Effects of intrathecal thyrotropin-releasing hormone (protirelin) in refractory depressed patients. Arch Gen Psychiatry. 1997 Mar;54(3):214-22. doi: 10.1001/archpsyc.1997.01830150034007. PMID: 9075462.
  2. Bunevicius R, Matulevicius V. Short-lasting behavioural effects of thyrotropin-releasing hormone in depressed women: results of placebo-controlled study. Psychoneuroendocrinology. 1993;18(5-6):445-9. doi: 10.1016/0306-4530(93)90019-h. PMID: 8416053.
  3. Callahan AM, Frye MA, Marangell LB, George MS, Ketter TA, L’Herrou T, Post RM. Comparative antidepressant effects of intravenous and intrathecal thyrotropin-releasing hormone: confounding effects of tolerance and implications for therapeutics. Biol Psychiatry. 1997 Feb 1;41(3):264-72. doi: 10.1016/s0006-3223(97)00372-7. PMID: 9024949.
  4. Watanave M, Matsuzaki Y, Nakajima Y, Ozawa A, Yamada M, Hirai H. Contribution of Thyrotropin-Releasing Hormone to Cerebellar Long-Term Depression and Motor Learning. Front Cell Neurosci. 2018 Dec 12;12:490. doi: 10.3389/fncel.2018.00490. PMID: 30618637; PMCID: PMC6299015.
  5. Boghosian JD, Luethy A, Cotten JF. Intravenous and Intratracheal Thyrotropin Releasing Hormone and Its Analog Taltirelin Reverse Opioid-Induced Respiratory Depression in Isoflurane Anesthetized Rats. J Pharmacol Exp Ther. 2018 Jul;366(1):105-112. doi: 10.1124/jpet.118.248377. Epub 2018 Apr 19. PMID: 29674333; PMCID: PMC5987997.
  6. Asai H, Watanabe Y, Yamauchi-Kohno R, Doi O. Reversal of hemorrhagic shock in rats using the metabolically stable thyrotropin-releasing hormone analog taltirelin hydrate. J Recept Signal Transduct Res. 2011 Dec;31(6):416-22. doi: 10.3109/10799893.2011.625427. Epub 2011 Nov 1. PMID: 22044177.
  7. Fliers E, Guldenaar SE, Wiersinga WM, Swaab DF. Decreased hypothalamic thyrotropin-releasing hormone gene expression in patients with nonthyroidal illness. J Clin Endocrinol Metab. 1997 Dec;82(12):4032-6. doi: 10.1210/jcem.82.12.4404. PMID: 9398708.
  8. Mellow AM, Sunderland T, Cohen RM, Lawlor BA, Hill JL, Newhouse PA, Cohen MR, Murphy DL. Acute effects of high-dose thyrotropin releasing hormone infusions in Alzheimer’s disease. Psychopharmacology (Berl). 1989;98(3):403-7. doi: 10.1007/BF00451695. PMID: 2501817.
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11 reviews for TRH Thyrotropin (Protirelin) (25mg)

  1. Gigi Perry

    No instructions unfortunately but google came through

  2. Samuel Chiang

    Im a returning customer and I havent been let down yet

  3. Diana Sterling

    Biotech Peptides has been an amazing find. So far it has been a promising company to do business with. Looking forward to seeing what they have in store in the long run for loyal repeat customers!

  4. AJ Park

    Was pleasantly surprised with the whole process. Easy going and quick.

  5. Dena Ward

    Biotech Peptides is my go to peptide company! I recommend it to colleagues whenever I get the chance! They never seem to fail me

  6. Shea Rain

    No breaks or anything with my peptides. Thanks!

  7. Johnathan Mendoza

    Never encountered a moment where my peptides where out of stock! Love that as waiting for restocks could be annoying.

  8. bradley burr

    Been a customer since the start! Quality and service has never gone down.

  9. Arnold Alexander

    The cost is worth it. Quality peptides and fantastic sales as well.

  10. Steve M.

    Jaimie was awsome and was able to correct my email as I made a typo. Order is coming in soon and can’t wait to start on my research.

  11. Jacob Morris

    New to the peptide game so decided to call in to ask some questions about its storage and such. Danny was great and even sent me a discount code for my next order.

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