01884naa a2200253 a 450000100080000000500110000800800410001910000260006024501850008626000090027152009950028065000180127565000250129365000130131865300280133165300180135965300210137770000210139870000190141970000200143870000210145870000250147977301260150421779192025-08-12       2025    bl uuuu     u00u1 u    #d1 aOLIVEIRA, R. G. de S.  aEffects of gonadorelin on gonadotropin expression, plasma sex steroid concentrations and ovarian follicle dynamics in mature tambaqui (Colossoma macropomum).h[electronic resource]  c2025  aIn tambaqui (Colossoma macropomum), a rheophilic Amazonian fish of significant aquaculture importance that typically fails to spawn under captive conditions, gonadorelin has demonstrated potential in inducing ovulation and enabling strip spawning. However, the molecular mechanisms underlying gonadorelin action, particularly on the transcriptional regulation of follicle-stimulating hormone (fshβ) and luteinizing hormone (lhβ), remain poorly understood and warrant further investigation. The present study aimed to investigate the efficacy of this synthetic drug in modulating the expression of gonadotropins and in enhancing circulating concentrations of 17β-estradiol (E2), 17α-hydroxyprogesterone (17α-OHP), and testosterone (T) in tambaqui; as well as its effects on the developmental dynamics and maturation stages of ovarian follicles. Gonadorelin at 60 μg kg−1 body weight had no statistical effect on lhβ expression, but decreased fshβ expression in females (p = 0.021).  aGonadotropins  aColossoma Macropomum  aTambaqui  aArtificial reproduction  aGnRH analogue  aNeotropical fish1 aMORAIS, I. S. de1 aPAIXÃO, R. V.1 aBANDEIRA, I. C.1 aDUNCAN, W. L. P.1 aO'SULLIVAN, F. L. A.  tComparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biologygv. 279, art. 111126, Aug.-Sept. 2025.