Analgesic effect of central relaxin receptor activation on persistent inflammatory pain in mice: behavioral and neurochemical data.

Abboud C, Brochoire L, Drouet A, Hossain MA, Hleihel W, Gundlach AL, Landry M

Pain reports16 Jun 2021Cited by 7 (Europe PMC)

PMID34159282PMCIDPMC8213244DOI10.1097/pr9.0000000000000937PepBankPUB-34159282

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Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: CC BY-NC. Results still quote short attributed sentences.

Results from this study4

2 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Efficacy outcome
In mice with CFA-induced inflammation, B7‑33 transiently reduced mechanical sensitivity only in the CFA-injected hind paw at 30 minutes.
In plain wordsIn mice with paw inflammation, B7‑33 briefly reduced mechanical sensitivity only in the inflamed paw at 30 minutes.
Peptide
B7-33 (single-chain relaxin-2 analog)
Outcome
DecreaseMechanical sensitivity
Study
mousen: not reported in source
Complete Freund Adjuvant hind-paw inflammation
Outcome group
Pain · Nervous system and cognition
Studied dose
Dose not stated · intracerebroventricularAs given in this study (mouse).
Source sentences
Summary
Both H2-relaxin and B7-33 produced a strong, but transient, reduction in mechanical and thermal sensitivity of the CFA-injected hind paw alone, at 30 minutes postinjection.
2 context sentences(design, population, supporting numbers)
Summary · context
Mice were injected with Complete Freund Adjuvant (CFA) into a hind paw.
Summary · context
After 4 days, the RXFP1 agonist peptides, H2-relaxin or B7-33, ± the RXFP1 antagonist, B-R13/17K-H2, were injected into the lateral cerebral ventricle, and mechanical and thermal sensitivity were assessed at 30 to 120 minutes.
Report a problemFND-3415928201
02AnimalAnimal study (in vivo)Efficacy outcome
In mice with CFA-induced inflammation, B7‑33 transiently reduced thermal sensitivity only in the CFA-injected hind paw at 30 minutes.
In plain wordsIn mice with paw inflammation, B7‑33 briefly reduced heat sensitivity only in the inflamed paw at 30 minutes.
Peptide
B7-33 (single-chain relaxin-2 analog)
Outcome
DecreaseThermal sensitivity
Study
mousen: not reported in source
Complete Freund Adjuvant hind-paw inflammation
Outcome group
Pain · Nervous system and cognition
Studied dose
Dose not stated · intracerebroventricularAs given in this study (mouse).
Source sentences
Summary
Both H2-relaxin and B7-33 produced a strong, but transient, reduction in mechanical and thermal sensitivity of the CFA-injected hind paw alone, at 30 minutes postinjection.
2 context sentences(design, population, supporting numbers)
Summary · context
Mice were injected with Complete Freund Adjuvant (CFA) into a hind paw.
Summary · context
After 4 days, the RXFP1 agonist peptides, H2-relaxin or B7-33, ± the RXFP1 antagonist, B-R13/17K-H2, were injected into the lateral cerebral ventricle, and mechanical and thermal sensitivity were assessed at 30 to 120 minutes.
Report a problemFND-3415928202

Studies that did not test the peptide alone2

In this study, B7-33 (single-chain relaxin-2 analog) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking B7-33 (single-chain relaxin-2 analog).

03AnimalNot a test of B7-33 (single-chain relaxin-2 analog) aloneAnimal study (in vivo)Efficacy outcome
In mice with CFA-induced inflammation, RXFP1 antagonist coinjection blocked mechanical analgesia from the tested agonist peptides, including B7‑33.
In plain wordsIn mice with paw inflammation, antagonist coinjection blocked mechanical pain relief from the tested agonists, including B7‑33.
Peptide
B7-33 (single-chain relaxin-2 analog)
Outcome
DecreaseAntagonist blockade of mechanical analgesia
Study
mousen: not reported in source
Complete Freund Adjuvant hind-paw inflammation
Comparator
Agonist without antagonist
Outcome group
Pain · Nervous system and cognition
Source sentences
Summary
Notably, coinjection of B-R13/17K-H2 blocked mechanical, but not thermal, analgesia.
2 context sentences(design, population, supporting numbers)
Summary · context
Mice were injected with Complete Freund Adjuvant (CFA) into a hind paw.
Summary · context
After 4 days, the RXFP1 agonist peptides, H2-relaxin or B7-33, ± the RXFP1 antagonist, B-R13/17K-H2, were injected into the lateral cerebral ventricle, and mechanical and thermal sensitivity were assessed at 30 to 120 minutes.
In this study, B7-33 (single-chain relaxin-2 analog) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking B7-33 (single-chain relaxin-2 analog).
Report a problemFND-3415928203
04AnimalNot a test of B7-33 (single-chain relaxin-2 analog) aloneAnimal study (in vivo)Efficacy outcome
In mice with CFA-induced inflammation, RXFP1 antagonist coinjection did not block thermal analgesia from the tested agonist peptides, including B7‑33.
In plain wordsIn mice with paw inflammation, antagonist coinjection did not block thermal pain relief from the tested agonists, including B7‑33.
Peptide
B7-33 (single-chain relaxin-2 analog)
Outcome
No significant changeAntagonist blockade of thermal analgesia
Study
mousen: not reported in source
Complete Freund Adjuvant hind-paw inflammation
Comparator
Agonist without antagonist
Outcome group
Pain · Nervous system and cognition
Source sentences
Summary
Notably, coinjection of B-R13/17K-H2 blocked mechanical, but not thermal, analgesia.
2 context sentences(design, population, supporting numbers)
Summary · context
Mice were injected with Complete Freund Adjuvant (CFA) into a hind paw.
Summary · context
After 4 days, the RXFP1 agonist peptides, H2-relaxin or B7-33, ± the RXFP1 antagonist, B-R13/17K-H2, were injected into the lateral cerebral ventricle, and mechanical and thermal sensitivity were assessed at 30 to 120 minutes.
In this study, B7-33 (single-chain relaxin-2 analog) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking B7-33 (single-chain relaxin-2 analog).
Report a problemFND-3415928204

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
22 Oct 2026, 02:25 UTC
Study results updated
Version 1
21 Oct 2026, 18:59 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

Publication types

Keywords

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