The mechanisms by which chronic infusion of an initially subpressor low dose of angiotensin II (ANG II) causes a progressive and sustained hypertension remain unclear. In conscious sheep (n = 6), intravenous infusion of ANG II (2 microg/h) gradually increased mean arterial pressure (MAP) from 82 +/- 3 to 96 +/- 5 mmHg over 7 days (P < 0.001). This was accompanied by peripheral vasoconstriction; total peripheral conductance decreased from 44.6 +/- 6.4 to 38.2 +/- 6.7 ml.min(-1).mmHg(-1) (P < 0.001). Cardiac output and heart rate were unchanged. In the regional circulation, mesenteric, renal, and iliac conductances decreased but blood flows were unchanged. There was no coronary vasoconstriction, and coronary blood flow increased. Ganglion blockade (125 mg/h hexamethonium for 4 h) reduced MAP by 13 +/- 1 mmHg in the control period and by 7 +/- 2 mmHg on day 8 of ANG II treatment. Inhibition of central AT(1) receptors by intracerebroventricular infusion of losartan (1 mg/h for 3 h) had no effect on MAP in the control period or after 7 days of ANG II infusion. Pressor responsiveness to incremental doses of intravenous ANG II (5, 10, 20 microg/h, each for 15 min) was unchanged after 7 days of ANG II infusion. ANG II caused no sodium or water retention. In summary, hypertension due to infusion of a low dose of ANG II was accompanied by generalized peripheral vasoconstriction. Indirect evidence suggested that the hypertension was not neurogenic, but measurement of sympathetic nerve activity is required to confirm this conclusion. There was no evidence for a role for central angiotensinergic mechanisms, increased pressor responsiveness to ANG II, or sodium and fluid retention.

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Aim During the first wave of coronavirus disease 2019 (COVID‐19), visiting guidelines in neonatal units changed to maintain the health and safety of staff, neonates, and families. In the neonatal intensive care unit/special care nursery (NICU/SCN), restrictions were placed on parental contact and extended family excluded. Our team was interested in evaluating the effect of these restrictions on parental stress and discharge confidence. Methods A prospective descriptive study utilising survey methodology was undertaken. The survey was developed and previously used by the NICU research group to evaluate parental knowledge and understanding, parental role, communication, and parental stress (admission/discharge). We have also included a section regarding COVID19 visiting restrictions (ETH.2020.LRE.00124). The survey used a five‐level Likert scale. Statistical analysis was completed using SPSS version 21. Results Notably, 33 surveys were returned. Results showed visiting restrictions reduced social contact between partners 26/33 (84%), with their other children 14/16 (87.5%) and extended family 28/33 (84.8%). Parents indicated that they had high levels of confidence in understanding their babies' medical needs (78–93%) and gaining hands‐on experience caring for their baby (87–100%). However, 11/33 (33%) of parents reported concerns with discharge processes and gaining consistent information as challenges during their baby's admission. Notably, 17/33 (51.5) stated their NICU/SCN experience had been very to extremely stressful. Parents openly described how the restrictions had affected their mental/emotional health identifying the need to treat parents as one unit, and a gap in the psychological support available for families. Conclusion Support services and consistency of communication with NICU/SCN families need to be enhanced and prioritised during periods of restrictions, especially peri‐discharge.