EVIDENCE AGAINST AN INTERACTION OF ANGIOTENSIN II WITH THE SYMPATHETIC NERVOUS SYSTEM IN MAN

Animal experiments indicate that angiotensin II can, under some circumstances stimulate the sympathetic nervous system at a number of different sites. In order to determine whether such a relationship of the renin-angiotensin and sympathetic nervous system exists in man, we increased (by intravenous infusion), or decreased (by administering the oral converting enzyme inhibitor captopril) circulating angiotensin II levels and monitored plasma adrenaline and nor-adrenaline responses. Angiotensin II infusions did not increase plasma catechol-amines, and lowering of angiotensin II by captopril treatment in patients with severe hypertension or congestive heart failure failed to alter plasma adrenaline or nor-adrenaline levels. Whether physiological levels of angiotensin II are capable of interacting directly with the sympathetic nervous system in man remains to be demonstrated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73600/1/j.1365-2265.1981.tb00684.x.pd

Minor Abnormalities of Testis Development in Mice Lacking the Gene Encoding the MAPK Signalling Component, MAP3K1

In mammals, the Y chromosome is a dominant male determinant, causing the bipotential gonad to develop as a testis. Recently, cases of familial and spontaneous 46,XY disorders of sex development (DSD) have been attributed to mutations in the human gene encoding mitogen-activated protein kinase kinase kinase 1, MAP3K1, a component of the mitogen-activated protein kinase (MAPK) signal transduction pathway. In individuals harbouring heterozygous mutations in MAP3K1, dysregulation of MAPK signalling was observed in lymphoblastoid cell lines, suggesting a causal role for these mutations in disrupting XY sexual development. Mice lacking the cognate gene, Map3k1, are viable and exhibit the eyes open at birth (EOB) phenotype on a mixed genetic background, but on the C57BL/6J genetic background most mice die at around 14.5 dpc due to a failure of erythropoiesis in the fetal liver. However, no systematic examination of sexual development in Map3k1-deficient mice has been described, an omission that is especially relevant in the case of C57BL/6J, a genetic background that is sensitized to disruptions to testis determination. Here, we report that on a mixed genetic background mice lacking Map3k1 are fertile and exhibit no overt abnormalities of testis development. On C57BL/6J, significant non-viability is observed with very few animals surviving to adulthood. However, an examination of development in Map3k1-deficient XY embryos on this genetic background revealed no significant defects in testis determination, although minor abnormalities were observed, including an increase in gonadal length. Based on these observations, we conclude that MAP3K1 is not required for mouse testis determination. We discuss the significance of these data for the functional interpretation of sex-reversing MAP3K1 mutations in humans

Communicating Predator Free 2050 with children: A literature review on age-appropriate conservation action

In response to the documented decline of New Zealand’s native flora and fauna in the face of introduced predators, the New Zealand Government has set out to eradicate several species of mammalian predators by the year 2050 through its Predator-Free 2050 initiative (PF2050). This collaborative, nation-wide programme reflects an investment in a biological and social movement that depends on cross-sector cooperation and community partnership, multigenerational awareness, engagement and action. Hence there is legitimate public and scholarly interest in the issue of how best to convey key predator and pest control themes within conservation communication targeted at children. In particular, concerns have been raised about the potential effects of these messages on the development of empathy and healthy attitudes toward stewardship of nature as a whole. This commissioned report explores the literature on this theme, starting with the literature on children’s empathy for nature and animals, before looking to the research on the development of moral reasoning and empathy in children. The report will then draw on these two bodies of literature – along with research on communicating complex issues with children – to discuss how PF2050 messages can be communicated to children in an age-appropriate context. The report concludes with a set of principles intended to help guide conservation educators in designing predator control education programmes for childre

Behaviour change interventions to facilitate forest trail users’ biosecurity compliance

Natural resource management can struggle with increased visitation that inadvertently deteriorates the environment. In Aotearoa New Zealand, visitors to kauri forests are spreading a lethal soil pathogen resulting in cultural and conservation risk. While public awareness of kauri dieback disease is growing, compliance at hygiene stations has not similarly increased. To overcome this apparent knowledge-behaviour gap, five interventions (ambassadors, normative messaging, watching eye effect, hazard perception, and pledge board) were evaluated for their impact on visitor compliance with footwear/equipment cleaning behaviour. Behavioural observations (n = 10,536) and intercept surveys (n = 3,061) were collected. Ambassadors resulted in increased compliance for both visitors and local trail users. The pledge board resulted in increased compliance for local trail users only and normative message increased compliance at one visitor site. Hazard perception and watching eye resulted in a decrease in compliance behaviour. This research demonstrates the need for careful assessment of interventions designed to mitigate the impacts of visitors to conservation areas. The success of the ambassador intervention, the pledge board for locals and, to a lesser extent, the normative message at one location, offer field-based empirical evidence supporting the use of social norms in communication approaches aimed at influencing visitor behaviour in natural resource settings

Adaptation of the hypothalamo-pituitary adrenal axis to chronic exercise stress

Repeated acute or chronic exposure to a particular stress results in adaptation whereby the hypothalamopituitary adrenal (HPS) axis becomes less responsive to subsequent or continued exposure to that particular stress. To investigate the adaptive changes that occur in the HPA axis in response to chronic stress in humans, we studied the effect of chronic exercise stress on basal activity of the HPA axis in six highly trained male ultramarathon athletes and six healthy male controls matched for body mass index. After 3-5 of abstention from intense physical activity, the subjects were admitted to a metabolic study ward at 1600 h. Peripheral blood was sampled initially at 0300 h, at 20-min intervals from 0400 to 0900 h, hourly from 0900 to 1200 h, and then every 2 h from 1200 to 1600 h. A 24-h urine collection was completed during the admission. Peripheral blood adrenocorticotropic hormone (ACTH) was measured by radioimmunoassay. Plasma and urinary cortisol were measured by enzyme-linked immunoassay. Plasma and injury cortisol were measured by enzyme-linked immunosorbent assay (ELISA). Plasma ACTH and cortisol levels showed the expected diurnal change in athletes and control subjects (P = 0.00001). However, the early morning ACTH and cortisol surge occurred earlier in the athletes than in the controls (P = 0.026). Plasma ACTH levels were significantly higher in the athletes than in the control subjects (P = 0.0026). There was, however, no significant overall difference in plasma cortisol levels between the athletes and the control subjects, and urinary excretion of free cortisol was similar in the two groups. These data show that intense physical training leads to adaptive changes in basal HPA function, including a phase shift and increased pituitary in basal HPA function, including a phase shift and increased pituitary ACTH secretion, but also blunting of the adrenal cortisol response.Wittert, Gary A.; Livesey, John H.; Espiner, Eric A.; Donald, Richard A

The Forgotten Islands: Monitoring Tourist Numbers and Managing Tourism Impacts on New Zealand’s Subantarctic Islands

Situated to the south of New Zealand in the Southern Ocean are the New Zealand Subantarctic Islands, comprising the Auckland, Campbell, Antipodes, Snares and Bounty Islands. Sometimes referred to as the ‘Forgotten Islands’, these island groups are among the most remote and hostile within New Zealand waters. Yet, as they harbour some of the country’s most unique biodiversity and contain some of the world’s least modified landforms, they were recognized in 1998 with the designation of World Heritage Area status. It is not surprising therefore that the Islands have long appealed to visitors wishing to explore and understand the Islands’ rich natural and cultural environments. Typically, fare-paying tourists arrive by sea in small- to medium-sized expedition-style cruise vessels, although in recent years, the number of small vessels, such as yachts and sail boats, has increased. The most recent Conservation Management Strategy (2016) proposes developing and implementing a visitor monitoring programme to determine the effects of visitors on the natural and cultural environment, as well as on the visitor experience itself. However, there is only piecemeal data published on visitor numbers (especially since the mid-1990s) upon which to base visitor monitoring, and there is only limited evidence regarding the range of possible impacts visitors may have, including direct and indirect impact on wildlife, soils, and vegetation. In order to address this gap in knowledge, this case study draws on stakeholder interviews (n = 4), and a range of secondary sources (including visitor statistics from the Department of Conservation, tour operators and other published works) to provide an overview and update on visitation to the Islands, including site-specific data, an assessment of tourist impacts, and how impacts are currently monitored and managed