Hypothalamic-pituitary-adrenocortical (HPA) axis data, such as low plasma cortisol concentrations in spite of increased corticotropin-releasing hormone (CRH) levels in patients with posttraumatic stress disorder (PTSD), are difficult to interpret. Atrial natriuretic peptide (ANP) may be an explanatory link in the neuroendocrine pathophysiology of the disorder, since it is a neuromodulator with antianxiety effects that inhibits HPA activity at multiple levels. Seventeen patients with chronic PTSD and 17 healthy control subjects were given 100 µg of human CRH at 3 p.m. ANP, adrenocorticotropic hormone (ACTH), and cortisol levels in plasma as well as blood pressure and heart rate were measured during basal conditions and after CRH stimulation. Basal ANP levels were significantly lower in PTSD patients in comparison with normal controls, but the response to CRH was undistinguishable. In contrast to our expectation, no significant differences in basal or CRH-stimulated ACTH or cortisol parameters could be observed. Systolic and diastolic blood pressures at baseline and after CRH were significantly elevated in PTSD patients. All group differences remained significant after controlling for basal blood pressure and/or body mass index. Our data do not support a role of ANP in abnormal HPA axis regulation in PTSD. However, the persistently low ANP plasma levels in PTSD patients despite elevated blood pressure may serve to facilitate anxiety behavior and have adverse long-term cardiovascular consequences. Further studies to assess ANP secretion in PTSD patients and to clarify its pathophysiological impact are needed.

No abstract

No abstract

When people learn from each other and change their behavior accordingly, this is called social learning. COVID-19 not only taught us new habits to limit contagion, imposed restrictions also limited people’s everyday practices and behavior. Our study aims to analyze how (much) the pandemic may have incidentally fostered social learning of sustainability (SLS), representing a shift from rule-based behavior and forced behavior changes to more associative and potentially long-lasting sustainable behavior. To answer this question, we analyzed data from two mixed-method surveys with which we approached two customized samples in a higher education setting in Australia (n = 100) and Austria (n = 264). The findings show that in a higher education and, specifically, a university context, there are less sustainable practices evaluated as stable and “new normal” than assumed. Still, sustainability is more rule-related and less associative, predominantly in Australia. Nevertheless, a certain degree of awareness of what sustainable practices are can be observed mainly in Austria. As a broader implication, the study at hand leads to the conclusion that through COVID-19, sustainability at least became more tangible. Furthermore, universities as a specific institution have the potential to put sustainability higher on their agenda and take responsibility for social change. In the conclusion and outlook of the paper, limitations of the study as well as future research potential on social learning processes for sustainable development are presented and discussed.