Energetic dependence of NPY-induced LH secretion in a teleost fish (Dicentrarchus labrax).
The purpose of this work was to examine the role of energetic status in neuropeptide Y (NPY)-induced luteinizing hormone (LH) secretion and glucose metabolism in fish. Fasted juvenile sea bass (Dicentrarchus labrax) were injected intraperitoneally with pig (p) NPY or pNPY + glucose, whereas fed animals were injected with pNPY alone and plasma glucose, insulin, and LH levels were examined. pNPY alone or in combination with glucose was found to induce a dose-dependent increase in LH secretion in fasted animals. Similar LH responses to pNPY were observed in vitro in dispersed pituitary cells isolated from fed and fasted animals incubated in L-15 and restricted media. Injection of pNPY + glucose in fasted animals resulted in depletion of glucose. Insulin plasma levels decreased in fasted animals coinjected with pNPY + glucose but remained stable when NPY was administrated alone to fed and fasted animals. Results suggest that 1) NPY-induced LH secretion in fish is dependent on energetic status and 2) NPY is capable of modifying glucose metabolism.
Cerdá-Reverter
J M
JM
Department of Fish Reproductive Physiology, Instituto de Acuicultura de Torre de la Sal, Consejo Superior De Investigaciones Cientificas, 12595 Torre de la Sal, Castellón, Spain.
Sorbera
L A
LA
Carrillo
M
M
Zanuy
S
S
D000818:Animals; D001492:Bass / Q000097:blood / Q000502:physiology*; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D004435:Eating; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D005215:Fasting; D005947:Glucose / Q000378:metabolism*; D007328:Insulin / Q000097:blood / Q000378:metabolism; D000078790:Insulin Secretion; D007700:Kinetics; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D009478:Neuropeptide Y / Q000494:pharmacology*; D013552:Swine
D001786:Blood Glucose; D007328:Insulin; D009478:Neuropeptide Y; D007986:Luteinizing Hormone; D005947:Glucose