Further data on the development of SRIF-like immunoreactive nerve cell populations in the chick embryo brain stem. I. Medulla and pons.

Institute of Human Anatomy, University of Bari.
Bollettino della Società italiana di biologia sperimentale 06/1992; 68(5):321-8.
Source: PubMed


Further immunocytochemical analysis of the neuroblasts with SRIF-like immunoreactivity (ir) was carried out on the chick embryo medulla and pons. 5 or 100 microns rombencephalon sections were obtained from 60 White Leghorn chick embryos at stages (E = Embryonic days) ranging from E4 1/2 to E18 and incubated with rabbit polyclonal antibodies against synthetic cyclic Somatostatin-14, according to PAP-DAB technique. In the medulla and pons the ir appeared as from E12. From E12 to E13 1/2-E14 the ir distribution gradually changed. From E14 to E18 numbers and spatial arrangement of the positive neuroblast groups did not show substantial changes; in these respects the ir distributional pattern proved to be markedly different from the one observed by the Authors in adult animals. Moreover, from E13 to E15 the positive neuroblast density appeared to be higher than that of positive neurons in adults. These results are consistent with a possible SRIF local regulative role.

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    • "To date, most studies have focussed on changes at the peripheral level – plasma hormone concentrations or in vitro deiodinase activities (Thommes & Hylka 1977, Hylka et al. 1986, Galton & Hiebert 1987, Darras et al. 1992). Data on the ontogenetic appearance of hypothalamic factors in the chicken brain are, however, restricted to immunocytochemical studies (corticotropin-releasing hormone (CRH): Josza et al. 1986; TRH: Thommes et al. 1985; SRIH: Ambrosi et al. 1992). Accordingly, this paper describes the ontogenetic profile of hypothalamic TRH and SRIH concentrations during chick embryo development and posthatch growth. "
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