The effect of water quality on the immunoreactivity of stress-response cells and gonadotropin-secreting cells in the pituitary gland of Nile tilapia, Oreochromis niloticus
ABSTRACT The present experiments investigated the effect of water quality characteristics on the condition factor, the ovarian activity, cortisol level, and the immunoreactivity of stress‐response cells (adrenocorticotropic hormone; ACTH‐ and melanin stimulating hormone; MSH‐ and somatolactin; SL‐ s...
Saved in:
Published in | Journal of experimental zoology. Part A, Ecological genetics and physiology Vol. 323; no. 3; pp. 146 - 159 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
United States
Blackwell Publishing Ltd
01.03.2015
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | ABSTRACT
The present experiments investigated the effect of water quality characteristics on the condition factor, the ovarian activity, cortisol level, and the immunoreactivity of stress‐response cells (adrenocorticotropic hormone; ACTH‐ and melanin stimulating hormone; MSH‐ and somatolactin; SL‐ secreting cells) and gonadotropin (GTH)‐secreting cells in the pituitary gland of Nile tilapia, Oreochromis niloticus. After 3 months of exposure to mixtures of water from different sources (Tap and Lake Manzalah waters), with high levels of minerals and heavy metals, water quality affected the number, size, and immunostaining of stress‐response‐immunoreactive (ir) cells and GTH‐ir cells, which showed a dramatic decrease in their size. The integrated optical density (IOD) of immunoreactivity of MSH‐ and GTH‐ cells was significantly increased; however, it was significantly decreased for ACTH‐ and SL‐ cells. Also, high levels of cortisol were observed in females exposed to waters with high concentrations of minerals and heavy metals. In parallel, low values of gonadosomatic index (GSI%) and the ovarian histology revealed a decrease of maturing follicles concomitant with an increase of atretic follicles in females exposed to Lake Manzalah polluted water. Taken together, the increased activity of stress‐response‐ir pituitary cells, serum cortisol level and ovarian atretic follicles in response to elevated concentrations of minerals and heavy metals, supports the possible role of ACTH, MSH, and SL in the adaptive stress response of fish. Therefore, minerals and heavy metals must be considered when discussing tilapia aquaculture status. J. Exp. Zool. 323A: 146–159, 2015. © 2015 Wiley Periodicals, Inc. |
---|---|
Bibliography: | istex:691DA57908D4D855D212EE8B1807656D6FDB9DCA ArticleID:JEZ1901 ark:/67375/WNG-Z550G4D6-V ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1932-5223 1932-5231 |
DOI: | 10.1002/jez.1901 |