Unformatted text preview: (prob synergy)
in terms of effects on growth, as in mammals
• GH induces IGF-1 in salmon and other fishes.
• GH important for seawater adaptation in Coho
salmon: GH increase here does not cause IGF-1
and growth increase Salmon life-cycle 4 3/15/13 PRL, GH and SL in Bony Fishes
• SL is the most recent hormone to be identified in the pituitary
• Histological clues were provided by a novel type of cell in teleost
pars intermedia. These stained with periodic acid-Schiff (PAS)
reagent – hence “PIPAS” cells. These cells are sensitive to calcium
in their immediate environment.
• Salmonids lack PIPAS cells, but have SL immunopositive cells in the
• SL important for calcium balance, pigmentation, reproduction,
metabolism of phosphate and lipid. Smoltification and gonadal
maturation are correlated with high SL.
• Two subfamilies of SL: Slα and SLβ SL and pigmentation 5 3/15/13 PRL and GH in Amphibians
• PRL may act as GH in larval amphibians
• Even though PRL influences larval growth, it is anti-metamorphic in
anurans and caudate amphibians.
• PRL induces water-driven behavior in newts and salamanders,
along with secondary sexual characters (red eft behavior) • Eft video 6 3/15/13 PRL and GH in Amphibians
• Confusing, as PRL might be the larval form of GH
• GH might only operate in metamorphosed animals
• Frog GH and mammalian GH are very similar in structure and
physical properties, suggesting that GH is highly conserved
during evolution of the tetrapods.
• However, frog GH not as effective as bovine GH in rat tibia
• IGF has been seen in toads, but no link to GH or PRL known as
yet. Not well-studied. 7...
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This note was uploaded on 06/10/2013 for the course INTEG BIO 138 taught by Professor Bentley during the Spring '13 term at Berkeley.
- Spring '13