Effects of in vivo treatment with the dopamine antagonist pimozide and gonadotropin-releasing hormone agonist (GnRHa) on the reproductive axis of Senegalese sole (Solea senegalensis).
The Senegalese sole (Solea senegalensis) is a flatfish that exhibits severe reproductive dysfunctions in captivity. This study aimed at investigating the existence of a dopamine (DA) inhibitory tone on the reproductive axis of this species. Four groups of Senegalese sole breeders were treated with, saline (controls, CNT), the DA antagonist pimozide (PIM, 5 mg kg(-1)), gonadotropin-releasing hormone agonist (GnRHa, 40 μg kg(-1)) or a combination of PIM+GnRHa (COMB). Effects were evaluated on pituitary GnRH levels (ELISA), pituitary gonadotropin subunit transcript levels (qPCR), plasma levels of sex steroids and vitellogenin (ELISA), gonad development (histology), spermiation and egg production. The GnRHa treatment induced egg release and stimulated testis maturation. In males, PIM did not affect pituitary GnRH content, but enhanced GnRHa-induced pituitary GPα transcripts and modified plasma androgen levels; moreover, PIM stimulated spermatogenesis and milt production, both alone and combined with GnRHa. In females, PIM did not affect pituitary and plasma endocrine parameters and did not affect egg production and fertilization success of the broodstock, either alone or in the combined treatment. In conclusion, data indicated the existence of a DA inhibition in mature males, which would be absent or weakly expressed in females.
Institute of Aquaculture of Torre la Sal, Spanish Council for Scientific Research (CSIC), 12595-Ribera de Cabanes, Castellón, Spain.
José M
JM
Guzmán
Rosa
R
Cal
Angel
A
García-López
Olvido
O
Chereguini
Katherine
K
Kight
Mercedes
M
Olmedo
Carmen
C
Sarasquete
Constantinos C
CC
Mylonas
José B
JB
Peleteiro
Yonathan
Y
Zohar
Evaristo L
EL
Mañanós
D000818:Animals; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004958:Estradiol / Q000097:blood; D005260:Female; D005298:Fertility / Q000187:drug effects; D005412:Flatfishes / Q000502:physiology*; D037201:Follicle Stimulating Hormone, beta Subunit / Q000235:genetics / Q000378:metabolism; D015292:Glycoprotein Hormones, alpha Subunit / Q000235:genetics / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006066:Gonads / Q000187:drug effects* / Q000502:physiology; D037101:Luteinizing Hormone, beta Subunit / Q000235:genetics / Q000378:metabolism; D008297:Male; D010868:Pimozide / Q000494:pharmacology*; D010902:Pituitary Gland / Q000187:drug effects* / Q000502:physiology; D013076:Sperm Count; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood; D014158:Transcription, Genetic; D014819:Vitellogenins / Q000097:blood
D018492:Dopamine Antagonists; D037201:Follicle Stimulating Hormone, beta Subunit; D015292:Glycoprotein Hormones, alpha Subunit; D037101:Luteinizing Hormone, beta Subunit; D014819:Vitellogenins; D010868:Pimozide; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D004958:Estradiol; C003600:11-ketotestosterone