Immunocytochemical Distribution of GnRH in the Brain of Adult and Posthatching Great Tit Parus major and Ring Dove Streptopelia roseogrisea

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. . Wiley and Nordic Society Oikos are collaborating with JSTOR to digitize, preserve and extend access to Ornis Scandinavica. . 1992. Immunocytochemical distribution of GnRH in the brain of adult and posthatching Great Tit Parus major and Ring Dove Streptopelia roseogrisea. -Ornis Scand. 23: 222-232.This paper describes the appearance of GnRH-like immunoreactivity in the brain of adult and posthatching Ring Doves and Great Tits, with the goal of understanding the ontogeny of the gonadal-pituitary axis. To this end, we compared the distribution of GnRH immunostaining in adults, with that of posthatching birds of each species.The results of the adult study indicate the presence of a major group of GnRH immunoreactive perikarya in olfactory bulb, olfactory tubercle, nucleus accumbens, septal-preoptic-hypothalamic region, in the area surrounding the palial commissure, lateral hypothalamus, tuberal hypothalamus (Great Tit only) and near oculomotor nuclei nIII and nIV. Overall, these results are in good agreement with previous studies of GnRH-like immunoreactivity in other avian species, with some variations, most notably in the hypothalamic region. A surprising finding of the posthatching material was the absence of GnRH-like immunoreactive neurons and fibers in the septal-preoptic-hypothalamic region in the early days following hatching. The number and size of GnRH-containing neurons increased steadily in the post-hatching period from days 4-21. Also noteworthy was the absence of immunoreactive fibers in the median eminence and tuberal hypothalamic region before day 21 posthatching, suggesting that the hypothalamic-pituitarygonadal axis may not be mature before this time in the altricial and semialtricial species studied here.

Mast cells with gonadotropin-releasing hormone-like immunoreactivity in the brain of doves.

“…Immunoreactive neurons were distributed in the dove brain as described (19). The nonneuronal cells in the MH were easily distinguishable from the fusiform immunoreactive neurons of the preoptic area.…”

“…If secretion does take place, it would presumably result in release of histamine and a GnRH-like peptide, making these biologically active substances more available as courtship proceeds. Since axons immunoreactive for each of these substances are found within this area (19), it is reasonable to suppose that specific histamine and GnRH receptors are also present.…”

Prolactin Receptors in Dove Brain: Autoradiographic Analysis of Binding Characteristics in Discrete Brain Regions and Accessibility to Blood-Borne Prolactin

“…However, con centrated PRL binding activity is present in brain regions that have been implicated as part of the neural substrate 744 Buntin/Ruzycki/Witebsky Prolactin Receptors in Brain underlying some of the physiological and behavioral changes that occur following central or peripheral admin istration of PRL in this species. These include the PVN, VMN, and LHy for feeding behavior [27][28][29]; the POA, SL, BPC, LHy, and tuberal hypothalamus for gonadotro pin regulation [30][31][32], and the POA for parental behav ior [5,33,34], Whether these brain sites actually partici pate in PRL-induced changes in behavior and neuroen docrine function has yet to be directly tested in most cases. However, a recent intracranial injection study sug gests that the VMN (and possibly the POA) is an impor tant site of PRL action in promoting feeding activity in doves [35], Similarly, the possibility that PRL acts at least in part on the POA to promote parental behavior in verte brates is strengthened by recent evidence that direct injec tion of PRL into the POA facilitates maternal behavior in steroid-primed female rats [5] and by the observation that PRL binding activity in the POA is higher in parental …”

Confocal laser scanning and electron-microscopic analyses of the relationship between VIP-like and GnRH-like-immunoreactive neurons in the lateral septal-preoptic area of the pigeon

“…The distribution of gonadotropin-releasing hormone (GnRH)-ir perikarya and fibers in the avian brain has been repeatedly investigated (Oksche 1978;Blähser 1984;Foster et al 1987;Mikami et al 1988;Sherwood et al 1988;Kuenzel and Blähser 1991;Panzica et al 1992;Silver et al 1992;Millam et al 1993;Muske 1993;van Gils et al 1993). Irrespective of some species differences, these studies have shown a general morphological pattern with numerous perikarya being localized in the lateral septal-preoptic region.…”