Morphine attenuates testosterone response to central injection of kisspeptin in male rats.

Mahmoudi F, Khazali H, Janahmadi M

International journal of fertility & sterility8 Jul 2014Cited by 6 (Europe PMC)

PMID25083187PMCIDPMC4107696PepBankPUB-25083187

Summary

BackgroundKisspeptin and naloxone stimulate the reproductive axis while morphine inhibits its function. We have investigated the effect of central injection of kisspeptin-10 on mean plasma testosterone concentration in morphine or naloxone pretreated rats.Materials and methodsIn this experimental study, 60 male Wistar rats that were divid- ed into 12 groups (n=5 per group) received saline, kisspeptin (1 nmol, ICV), naloxone (2 mg/kg, subcutaneously), morphine (5 or 10 mg/kg, sc) or co-administrations of kisspeptin, morphine and naloxone at 09:00 - 09:30. In the co-administrated groups, kisspeptin was injected 15 minutes following morphine or naloxone injections. Blood samples were collected 60 minutes following injections via the tail vein. Plasma testosterone concentration was measured by a rat testosterone ELISA kit.ResultsCentral injection of kisspeptin or subcutaneous injection of naloxone significantly increased the mean plasma testosterone concentration compared to saline while subcutaneous injections of different doses of morphine (5 or 10 mg/kg) significantly decreased testosterone compared to saline. The results revealed that morphine significantly attenuated the testosterone increase after kisspeptin injection compared to kisspeptin while a stimulatory additive effect was observed in the kisspeptin/naloxone group compared to either naloxone or kisspeptin.ConclusionMorphine and kisspeptin systems may interact with each other to control the hypothalamic-pituitary-gonadal (HPG) axis.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study3

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

01AnimalAnimal study (in vivo)Efficacy outcome
In male Wistar rats, central injection of kisspeptin‑10 significantly increased mean plasma testosterone compared with saline.
In plain wordsIn male rats, kisspeptin‑10 injected into the brain raised blood testosterone more than saline did.
Peptide
Kisspeptin-10
Outcome
IncreasePlasma testosterone after central kisspeptin-10
Study
ratn = 5
Male Wistar rats
Comparator
Saline
Outcome group
Sex hormones and fertility · Endocrine and hormones
Studied dose
1 nmol · ICVAs given in this study (rat).
Source sentences
Summary
Central injection of kisspeptin or subcutaneous injection of naloxone significantly increased the mean plasma testosterone concentration compared to saline
1 context sentence(design, population, supporting numbers)
Summary · context
In this experimental study, 60 male Wistar rats that were divid- ed into 12 groups (n=5 per group) received saline, kisspeptin (1 nmol, ICV), naloxone (2 mg/kg, subcutaneously), morphine (5 or 10 mg/kg, sc) or co-administrations of kisspeptin, morphine and naloxone at 09:00 - 09:30.
Show in the study text Report a problemFND-2508318701

Studies that did not test the peptide alone2

In this study, Kisspeptin-10 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 Kisspeptin-10.

02AnimalNot a test of Kisspeptin-10 aloneAnimal study (in vivo)Efficacy outcome
In male Wistar rats, morphine significantly attenuated the testosterone increase after kisspeptin‑10 compared with kisspeptin alone.
In plain wordsIn male rats, morphine reduced the testosterone rise caused by kisspeptin‑10 compared with kisspeptin alone.
Peptide
Kisspeptin-10
Outcome
DecreaseTestosterone response to kisspeptin-10 with morphine pretreatment
Study
ratn = 5
Male Wistar rats
Comparator
Kisspeptin alone
Outcome group
Sex hormones and fertility · Endocrine and hormones
Source sentences
Summary
morphine significantly attenuated the testosterone increase after kisspeptin injection compared to kisspeptin
1 context sentence(design, population, supporting numbers)
Summary · context
In this experimental study, 60 male Wistar rats that were divid- ed into 12 groups (n=5 per group) received saline, kisspeptin (1 nmol, ICV), naloxone (2 mg/kg, subcutaneously), morphine (5 or 10 mg/kg, sc) or co-administrations of kisspeptin, morphine and naloxone at 09:00 - 09:30.
In this study, Kisspeptin-10 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 Kisspeptin-10.
Show in the study text Report a problemFND-2508318702
03AnimalNot a test of Kisspeptin-10 aloneAnimal study (in vivo)Efficacy outcome
In male Wistar rats, kisspeptin‑10 plus naloxone produced a stimulatory additive effect on testosterone compared with either naloxone or kisspeptin‑10 alone.
In plain wordsIn male rats, kisspeptin‑10 together with naloxone raised testosterone more than either one alone.
Peptide
Kisspeptin-10
Outcome
IncreaseTestosterone with kisspeptin-10 plus naloxone
Study
ratn = 5
Male Wistar rats
Comparator
Naloxone alone or kisspeptin-10 alone
Outcome group
Sex hormones and fertility · Endocrine and hormones
Source sentences
Summary
a stimulatory additive effect was observed in the kisspeptin/naloxone group compared to either naloxone or kisspeptin.
1 context sentence(design, population, supporting numbers)
Summary · context
In this experimental study, 60 male Wistar rats that were divid- ed into 12 groups (n=5 per group) received saline, kisspeptin (1 nmol, ICV), naloxone (2 mg/kg, subcutaneously), morphine (5 or 10 mg/kg, sc) or co-administrations of kisspeptin, morphine and naloxone at 09:00 - 09:30.
In this study, Kisspeptin-10 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 Kisspeptin-10.
Show in the study text Report a problemFND-2508318703

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
10 Oct 2026, 09:43 UTC
Study results updated
Version 1
9 Oct 2026, 03:04 UTC
First added · source update from Europe PMC

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