Sistema Renina-Angiotensina y función antehipofisaria: ¿Interacción endocrina o modulación paracrina?

La identificación de componentes del sistema renina-angiotensina y receptores celulares para angiotensina II (Ag II) en las células hipotalamo-hipofisarias sugirió una posible modulación de Ag II en la secreción-hipofisaria. Esta influencia ha sido confirmada posteriormente tanto «in vivo» como «in vitro» evidenciándose un efecto potenciador de la secreción de hormona de crecimiento (GH) y ACTH, y variable sobre la secreción de prolactina (PRL). No se han observado modificaciones «in vivo» sobre TSH y gonadotrofinas. La administración de inhibidores del enzima convertidor de la angiotensina disminuye los niveles periféricos de Ag II, produciendo una leve disminución de las concentraciones de GH y PRL. Sin embargo, el mecanismo por el que Ag II es capaz de modular la secreción adenohipofisaria aún permanece oscuro, desconociéndose si es un efecto directo o a través de factores hipotalámicos y, si existe una modulación endocrina o exclusivamente paracrina

Sarcoptic mange in wild ruminants in Spain: solving the epidemiological enigma using microsatellite markers

Background: In Spain, sarcoptic mange was first described in native wildlife in 1987 in Cazorla Natural Park, causing the death of nearly 95% of the local native population of Iberian ibex (Capra pyrenaica). Since then, additional outbreaks have been identified in several populations of ibex and other wild ungulate species throughout the country. Although the first epizootic outbreak in wildlife was attributed to the introduction of an infected herd of domestic goats, the origin and the cause of its persistence remain unclear. The main aims of this study are to understand (i) the number of Sarcoptes scabiei “strains” circulating in wild ruminant populations in Spain, and (ii) the molecular epidemiological relationships between S. scabiei and its hosts. Methods: Ten Sarcoptes microsatellite markers were used to characterize the genetic structure of 266 mites obtained from skin scrapings of 121 mangy wild ruminants between 2011 and 2019 from 11 areas in Spain. Results: Seventy-three different alleles and 37 private alleles were detected. The results of this study show the existence of three genetic strains of S. scabiei in the wild ruminant populations investigated. While two genetic clusters of S. scabiei were host- and geography-related, one cluster included multi-host mites deriving from geographically distant populations. Conclusions: The molecular epidemiological study of S. scabiei in wild ruminants in Spain indicates that the spreading and persistence of the parasite may be conditioned by host species community composition and the permissiveness of each host population/community to the circulation of individual “strains,” among other factors. Wildlife–livestock interactions and the role of human-driven introduction or trade of wild and domestic animals should be better investigated to prevent further spread of sarcoptic mange in as yet unaffected natural areas of the Iberian Peninsula

Sistema Renina-Angiotensina y función antehipofisaria: ¿Interacción endocrina o modulación paracrina?

La identificación de componentes del sistema renina-angiotensina y receptores celulares para angiotensina II (Ag II) en las células hipotalamo-hipofisarias sugirió una posible modulación de Ag II en la secreción-hipofisaria. Esta influencia ha sido confirmada posteriormente tanto «in vivo» como «in vitro» evidenciándose un efecto potenciador de la secreción de hormona de crecimiento (GH) y ACTH, y variable sobre la secreción de prolactina (PRL). No se han observado modificaciones «in vivo» sobre TSH y gonadotrofinas. La administración de inhibidores del enzima convertidor de la angiotensina disminuye los niveles periféricos de Ag II, produciendo una leve disminución de las concentraciones de GH y PRL. Sin embargo, el mecanismo por el que Ag II es capaz de modular la secreción adenohipofisaria aún permanece oscuro, desconociéndose si es un efecto directo o a través de factores hipotalámicos y, si existe una modulación endocrina o exclusivamente paracrina

Which are the main threats affecting the marine megafauna in the Bay of Biscay?

The marine environment faces an increasing number of threats, mainly driven by anthropogenic activities, that are causing growing impacts on marine species and processes. In Europe, the EU Marine Strategy Framework Directive (MSFD) aims to achieve or maintain Good Environmental Status (GES) of the European waters by 2020. The Directive specifically refers to biodiversity with the first of the eleven qualitative descriptors (proposed to help describe what GES should look like) being Biodiversity is maintained. For this descriptor, the status of several functional groups, including marine megafauna species, need to be assessed using criteria such as population size and condition, and mortality due to bycatch in fishing gear, that compare current values against agreed thresholds. To contribute to this process, we performed an assessment of the threats affecting the marine megafauna community (i.e. seabirds and cetaceans) in the Bay of Biscay synthesizing the available evidences and identifying the main threats affecting the marine megafauna to help prioritise the required management and conservation actions. We analysed 4,023 admissions of seabirds recorded during 2004–2016 from four Wildlife Rehabilitation Centres to obtain an initial quantitative assessment of the pressures exerted on seabirds. The main marine threats identified in the Spanish North Atlantic sub-region were cachexia (52.3%), exposure to crude oil (10%) and interaction with fishing gears (5.3%). When considering all threats together, the common guillemot, the yellow-legged gull, the northern gannet, the great cormorant and the razorbill were the main affected species. In addition, we summarised the available information to perform an updated qualitative assessment of the severity of the threats faced by seabirds and cetaceans. The qualitative assessment showed that cetaceans are especially vulnerable to bycatch, vessel collision, and pollution-related threats, whilst seabirds are particularly sensitive to oil spills, bycatch and marine litter. This type of assessment studies can aid in the identification of priority areas and/or species where management measures should be applied to ensure that the ultimate goal of the MSFD, sustainable conservation of the marine environment, is reached