Distribution, Characterization, and Growth Hormone- Releasing Activity of Pituitary Adenylate Cyclase- Activating Polypeptide in the European Eel, Anguilla anguilla*

• Main Authors: Montero, M, Yon, Laurent, Rousseau, K, Arimura, A, Fournier, A., Dufour, S., Vaudry, H.
• Other Authors: Neuroendocrinologie cellulaire et moléculaire, Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Fédératif de Recherches Multidisciplinaires sur les Peptides (IFRMP 23), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre de Lutte Contre le Cancer Henri Becquerel Normandie Rouen (CLCC Henri Becquerel)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-CHU Rouen, Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Différenciation et communication neuronale et neuroendocrine (DC2N), Laboratoire de Physiologie Générale et Comparée (LPGC), Centre National de la Recherche Scientifique (CNRS), Tulane University, Université du Québec à Montréal = University of Québec in Montréal (UQAM)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 1998
• Subjects: [SDV]Life Sciences [q-bio]; Sockeye; Anguilla anguilla; European eel
• Online Access: https://hal-normandie-univ.archives-ouvertes.fr/hal-01706421; https://hal-normandie-univ.archives-ouvertes.fr/hal-01706421/document; https://hal-normandie-univ.archives-ouvertes.fr/hal-01706421/file/Montero%20Endocrinology%201998.pdf

International audience The complementary DNA encoding pituitary adenylate cyclase-activating polypeptide (PACAP) has been cloned from two species of teleost fishes, the Sockeye salmon and the Thai catfish, and the amino acid sequence of PACAP has been determined in another teleost, the stargazer. However, to date, the detailed distribution of PACAP im-munoreactivity has never been investigated in the fish brain. In the present study, we have determined the localization of PACAP-im-munoreactive neurons in the central nervous system of a primitive teleost fish, the European eel Anguilla anguilla, using an antiserum raised against PACAP27. PACAP-positive perikarya were exclusively observed in the diencephalon, i.e. in the preoptic nucleus of the hy-pothalamus and in the dorsal and ventral nuclei of the thalamus. PACAP-immunoreactive fibers were detected in various areas of the brain, notably in the ventral telencephalon, the diencephalon, the mesencephalon, the cerebellar valvula, and the medulla oblongata. In addition, a dense accumulation of PACAP-containing nerve terminals was found in the pars distalis of the pituitary. The PACAP-like im-munoreactivity contained in the eel brain was characterized by HPLC analysis combined with RIA quantification. The major form of PACAP-immunoreactive material coeluted with mammalian PACAP38. Molecular cloning of the PACAP precursor has previously shown that in fish, PACAP and GH-releasing hormone (GHRH) originate from the same precursor. We have thus investigated the effects of PACAP and GHRH on GH secretion from eel pituitary cells in primary culture. Dose-response experiments revealed that PACAP27 and PACAP38 possessed the same efficacy, but PACAP38 was 12 times more potent than PACAP27 in stimulating GH release (ED 50 4.3 10 10 and 3.5 10 9 M, respectively). In contrast, GHRH, even at a high concentration (10 6 M), had no effect on GH release. Taken together, these data indicate that in the eel, PACAP may play a significant role in the regulation of somatotrope cells: 1) ...