Person:
Delgado Saavedra, María Jesús

Profile Picture
First Name
María Jesús
Last Name
Delgado Saavedra
URI
https://hdl.handle.net/20.500.14352/74517
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Biológicas
Department
Genética, Fisiología y Microbiología
Area
Fisiología
Identifiers
UCM identifierORCIDScopus Author IDDialnet IDGoogle Scholar ID

Filters

2015 - 201912020 - 20211
Reset filters

Settings

Author: Delgado Saavedra, María Jesús × Subject: 591.18 ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Anatomical distribution and daily profile of gper1b gene expression in brain and peripheral structures of goldfish (Carassius auratus)
    (Chronobiology International, 2015) Sánchez Bretaño, Aída; Gueguen, Marie-M.; Cano-Nicolau, Joel; Kah, Olivier; Alonso Gómez, Ángel Luis; Delgado Saavedra, María Jesús; Isorna Alonso, Esther
    The functional organization of the circadian system and the location of the main circadian oscillators vary through phylogeny. Present study investigates by in situ hybridization the anatomical location of the clock gene gPer1b in forebrain and midbrain, pituitary, and in two peripheral locations, the anterior intestine and liver, in a teleost fish, the goldfish (Carassius auratus). Moreover, the daily expression profiles of this gene were also studied by quantitative Real Time-PCR. Goldfish were maintained under a 12L–12D photoperiod and fed daily at 2 h after lights were switched on. A wide distribution of gPer1b mRNA in goldfish brain and pituitary was found in telencephalon, some hypothalamic nuclei (including the homologous to mammalian SCN), habenular nucleus, optic tectum, cerebellum and torus longitudinalis. Moreover, gPer1b expression was observed, for the first time in teleosts, in the pituitary, liver and anterior intestine. Day/night differences in gper1b mRNA abundance were found by in situ hybridization, with higher signal at nighttime that correlates with the results obtained by RT-PCR, where a rhythmic gPer1b expression was found in all tissues with acrophases at the end of the night. Amplitudes of gper1b rhythms vary among tissues, being higher in liver and intestine than in the brain, maybe because different cues entrain clocks in these locations. These results support the existence of functional clocks in many central and peripheral locations in goldfish coordinated, ticking at the same time.
  • Thumbnail Image
    Item
    Pituitary hormones mRNA abundance in the Mediterranean sea bass Dicentrarchus labrax: seasonal rhythms, effects of melatonin and water salinity
    (Frontiers in Physiology, 2021) Falcón, Jack; Herrero, María Jesús; Nisembaum, Laura Gabriela; Isorna Alonso, Esther; Peyric, Elodie; Beauchaud, Marilyn; Attia, Joël; Covès, Denis; Fuentès, Michel; Delgado Saavedra, María Jesús; Besseau, Laurence
    In fish, most hormonal productions of the pituitary gland display daily and/or seasonal rhythmic patterns under control by upstream regulators, including internal biological clocks. The pineal hormone melatonin, one main output of the clocks, acts at different levels of the neuroendocrine axis. Melatonin rhythmic production is synchronized mainly by photoperiod and temperature. Here we aimed at better understanding the role melatonin plays in regulating the pituitary hormonal productions in a species of scientific and economical interest, the euryhaline European sea bass Dicentrarchus labrax. We investigated the seasonal variations in mRNA abundance of pituitary hormones in two groups of fish raised one in sea water (SW fish), and one in brackish water (BW fish). The mRNA abundance of three melatonin receptors was also studied in the SW fish. Finally, we investigated the in vitro effects of melatonin or analogs on the mRNA abundance of pituitary hormones at two times of the year and after adaptation to different salinities. We found that (1) the reproductive hormones displayed similar mRNA seasonal profiles regardless of the fish origin, while (2) the other hormones exhibited different patterns in the SW vs. the BW fish. (3) The melatonin receptors mRNA abundance displayed seasonal variations in the SW fish. (4) Melatonin affected mRNA abundance of most of the pituitary hormones in vitro; (5) the responses to melatonin depended on its concentration, the month investigated and the salinity at which the fish were previously adapted. Our results suggest that the productions of the pituitary are a response to multiple factors from internal and external origin including melatonin. The variety of the responses described might reflect a high plasticity of the pituitary in a fish that faces multiple external conditions along its life characterized by marked daily and seasonal changes in photoperiod, temperature and salinity.