TY - JOUR
T1 - Expression of Na(+)-K(+)-ATPase in the brown trout, Salmo trutta: in vivo modulation by hormones and seawater
AU - Madsen, S S
AU - Jensen, M K
AU - Nhr, J
AU - Kristiansen, K
N1 - Keywords: Animals; Cattle; Female; Hormones; Male; RNA, Messenger; Recombinant Proteins; Salmon; Seawater; Sodium-Potassium-Exchanging ATPase; Trout; Xenopus laevis
PY - 1995
Y1 - 1995
N2 - Expression of the Na(+)-K(+)-ATPase alpha-subunit was investigated in the gill and trunk kidney of Salmo trutta. Groups of freshwater (FW) fish were treated with various hormones [cortisol: 3 x 4.0 micrograms/g; recombinant salmon growth hormone (rsGH): 3 x 0.25 micrograms/g; salmon prolactin (sPRL): 3 x 0.25 micrograms/g; recombinant bovine insulin-like growth factor-I (rbIGF-I): 2 x 0.01 micrograms/g; or 2 x 0.1 micrograms/g] or transferred to 25 parts per thousand seawater (SW) and sampled after 1, 2, 3, and 50 days. Total RNA was analyzed by Northern blotting using Xenopus laevis Na(+)-K(+)-ATPase alpha-subunit cDNA as probe. The probe detected a 3.8-kb transcript. Relative to untreated FW control fish, the abundance of alpha-subunit Na(+)-K(+)-ATPase mRNA in gill tissue increased 1.7-to 2.5-fold after treatment with cortisol, rsGH, and rbIGF-I and after transfer to SW. Na(+)-K(+)-ATPase enzyme activity was also significantly stimulated in these groups, except at 0.01 micrograms/g rbIGF-I. sPRL was without effect. In the kidney, alpha-subunit mRNA level and Na(+)-K(+)-ATPase activity were unaffected by hormone treatment and SW transfer. The results indicate that an increased abundance of alpha-subunit mRNA is part of the molecular mechanism behind the increased gill Na(+)-K(+)-ATPase activity induced by SW transfer, cortisol, GH, and IGF-I.
AB - Expression of the Na(+)-K(+)-ATPase alpha-subunit was investigated in the gill and trunk kidney of Salmo trutta. Groups of freshwater (FW) fish were treated with various hormones [cortisol: 3 x 4.0 micrograms/g; recombinant salmon growth hormone (rsGH): 3 x 0.25 micrograms/g; salmon prolactin (sPRL): 3 x 0.25 micrograms/g; recombinant bovine insulin-like growth factor-I (rbIGF-I): 2 x 0.01 micrograms/g; or 2 x 0.1 micrograms/g] or transferred to 25 parts per thousand seawater (SW) and sampled after 1, 2, 3, and 50 days. Total RNA was analyzed by Northern blotting using Xenopus laevis Na(+)-K(+)-ATPase alpha-subunit cDNA as probe. The probe detected a 3.8-kb transcript. Relative to untreated FW control fish, the abundance of alpha-subunit Na(+)-K(+)-ATPase mRNA in gill tissue increased 1.7-to 2.5-fold after treatment with cortisol, rsGH, and rbIGF-I and after transfer to SW. Na(+)-K(+)-ATPase enzyme activity was also significantly stimulated in these groups, except at 0.01 micrograms/g rbIGF-I. sPRL was without effect. In the kidney, alpha-subunit mRNA level and Na(+)-K(+)-ATPase activity were unaffected by hormone treatment and SW transfer. The results indicate that an increased abundance of alpha-subunit mRNA is part of the molecular mechanism behind the increased gill Na(+)-K(+)-ATPase activity induced by SW transfer, cortisol, GH, and IGF-I.
M3 - Journal article
C2 - 8594935
SN - 0002-9513
VL - 269
SP - R1339-45
JO - American Journal of Physiology
JF - American Journal of Physiology
IS - 6 Pt 2
ER -