Animal study (ewe lambs) · PMID 41953732

Relationship between kisspeptin-10, neurokinin B and dynorphin A in the course of normal and delayed puberty in ewes — VialBase Research

KP-10 and NKB concentrations positively correlated with age in both singleton and twin ewes

Last updated · 2026 · Szysiak N, Kosior-Korzecka U, Gregula-Kania M, Patkowski K, Fila M, Junkuszew A · Journal of Veterinary Research
Key findings
  • KP-10 and NKB concentrations positively correlated with age in both singleton and twin ewes
  • Negative correlation between KP-10/NKB and Dynorphin A
  • Singletons reached puberty (first ovulation) at 8 months; twins at 10 months
  • KNDy neuron system (Kisspeptin/NKB/Dynorphin) regulates puberty timing
  • Delayed puberty in twins associated with slower KP-10/NKB rise

PMID 41953732 — Kisspeptin and Puberty Timing in Ewes

Compound: Kisspeptin Citation: Szysiak N et al. J Vet Res. 2026;70(1):139-147. doi:10.2478/jvetres-2026-0010

Summary

Examined changes in plasma KP-10, neurokinin B (NKB), and dynorphin A (Dyn A) concentrations during puberty in singleton vs. twin ewe lambs, from 4-10 months of age.

Key Findings

  • KP-10 and NKB increase with age: Positive correlation (r = 0.86-0.89) in both groups
  • Dynorphin A decreases: Negative correlation with KP-10 (r = -0.55 to -0.98) and NKB (r = -0.89 to -0.94)
  • Puberty timing: Singletons at 8 months, twins delayed to 10 months
  • KNDy regulation: Confirms the KNDy neuron model — increasing kisspeptin/NKB “accelerator” + decreasing dynorphin “brake” triggers GnRH pulse generator activation

Relevance to Kisspeptin

Provides in vivo evidence for the KNDy neuron model of puberty initiation. The coordinated increase in kisspeptin and NKB with concurrent dynorphin decline represents the molecular switch for reproductive activation.

PubMed

See Also