The importance of the olfactory rosettes in maintaining pituitary prolactin and prolactin-releasing peptide levels during hyposmotic acclimation in silver sea bream (Sparus sarba)
- 作者：Anna K.Y. Kwong ; Norman Y.S. Woo ; normanwoo@cuhk.edu.hk
- 关键词：Olfactory rosette ; Prolactin ; Prolactin-releasing peptide ; Salinity
- 刊名：Comparative Biochemistry and Physiology - Part A ; Molecular & Integrative Physiology
- 出版年：2012
- 期刊代码：23_10956433
- 类别：abs
- 出版时间：April, 2012
- 卷：161
- 期：4
- 页码：456-462
- 文件大小：1007 K
摘要
A potential role of the olfactory rosettes in maintaining prolactin (PRL) and prolactin-releasing peptide (PrRP) levels was examined in the euryhaline silver sea bream (Sparus sarba). The olfactory rosettes were surgically removed in silver sea bream adapted to hypo- (6 ppt) and hyper-osmotic (33 ppt) salinities and the mRNA expression of the two previously identified freshwater-adapting factors, prolactin (PRL) and prolactin-releasing peptide (PrRP), in silver sea bream was measured. The elevation of pituitary PRL and PrRP mRNA expression levels as seen in 6 ppt-adapted fish was abolished by surgical removal of the olfactory rosettes. The PRL and PrRP expression levels in fish adapted to 6 ppt were significantly lowered following olfactory rosette removal. On the other hand, hypothalamic PrRP mRNA expression in 6 ppt-adapted fish did not change. Specific signals for Na+-K+-ATPase but not CFTR mRNA expression were detected in the surface layers of olfactory epithelial cells by in situ hybridization. The mRNA abundance of CFTR and Na+-K+-ATPase 伪 and 尾 subunits remained unchanged in the olfactory rosette of silver sea bream adapted to 0, 6, 12, 33 and 50 ppt for 4 weeks and in fish abruptly transferred from 33 ppt to 6 ppt. Data obtained from the olfactory rosette removal experiments suggest a possible role of the olfactory system for maintaining PRL and PrRP expression during hyposmotic acclimation in sea bream.