Expression of pejerrey gonadotropin-releasing hormone (pjGnRH): a study in higher teleostean fishes.

GUSTAVO SOMOZA,; DAVIS LESCHIED,; MIRANDA, LEANDRO ANDRES; LO NOSTRO, FABIANA; MAGLIULO CEPRIANO, LUCIA; ALEJANDRO MONTANER,; MARTIN SHREIBMAN,; JEAN RIVIER,; NANCY SHERWOOD,

BIOLOGY OF REPRODUCTION

SOC STUDY REPRODUCTION

Año: 2002 vol. 67 p. 18164 - 18171

0006-3363

Molecular variants of GnRH were characterized by reversephase, high-performance liquid chromatography from brain extracts of fish in three different orders: Synbranchiformes (swamp eel [Synbranchus marmoratus]), Cyprinidontiformes (platyfish [Xiphophorus maculatus] and green swordtail [X. helleri]), and Atheriniformes (Patagonia pejerrey [Odontesthes hatchery]). Also, pituitary gland extracts from the pejerrey O. bonariensis (Atheriniformes) were characterized. Eluted fractions were tested in radioimmunoassays with antisera specific to GnRH, including both antisera that detected only one form of GnRH and those that detected several forms. The results show that brain extracts obtained from all species contained the same three molecular forms of GnRH, which were immunologically and chromatographically undistinguishable from chicken GnRH-II, pejerrey GnRH (pjGnRH), and salmon GnRH. This study supports the hypothesis that expression of these three forms is common in different fish orders and that pjGnRH is the main regulator of pituitary function in these fish.