Abstract
In euryhaline teleost black porgy,
, the glucocorticoid receptor (
), growth hormone receptor (
), prolactin (
)-receptor (
), and sodium-potassium ATPase alpha subunit (
) play essential physiological roles in the osmoregulatory organs, including the gill, kidney, and intestine, during osmotic stress. The present study aimed to investigate the impact of pituitary hormones and hormone receptors in the osmoregulatory organs during the transfer from freshwater (FW) to 4 ppt and seawater (SW) and vice versa in black porgy. Quantitative real-time PCR (Q-PCR) was carried out to analyze the transcript levels during salinity and osmoregulatory stress. Increased salinity resulted in decreased transcripts of
in the pituitary,
and
in the gill, and
and
in the kidney. Increased salinity caused the increased transcripts of
in the gill and
in the intestine. Decreased salinity resulted in increased pituitary
, and increases in
and
in the gill, and
,
, and
in the kidney. Taken together, the present results highlight the involvement of
,
,
, and
in the osmoregulation and osmotic stress in the osmoregulatory organs (gill, intestine, and kidney). Pituitary
, and gill and intestine
are consistently downregulated during the increased salinity stress and vice versa. It is suggested that
plays a more significant role in osmoregulation than
in the euryhaline black porgy. Furthermore, the present results highlighted that the gill
transcript's role was solely to balance the homeostasis in the black porgy during salinity stress.