Plasma renin activity in primary and secondary depression

The Renin Angiotensin System and Bipolar Disorder: A Systematic Review

Bipolar Disorder (BD) is a chronic a multifactorial psychiatric illness that affects mood, cognition, and functioning. BD is associated with several psychiatric conditions as well clinical comorbidities, particularly cardiovascular diseases. The neurobiology of BD is complex and multifactorial and several systems have been implicated. Considering that the Renin Angiotensin System (RAS) plays an important role in cardiovascular diseases and that recently evidence has suggested its role in psychiatric disorders, the aim of the present study is to summarize and to discuss recent findings related to the modulation of RAS components in BD. A systematic search of the literature using the electronic databases MEDLINE and LILACS was conducted through March 2019. The search terms were: "Bipolar Disorder"; "Renin Angiotensin System"; "Angiotensin 2"; "Angiotensin receptors"; "Angiotensin 1-7"; "ACE"; "ACE2"; "Mas Receptor". We included original studies assessing RAS in BD patients. Two hundred twenty-two citations were initially retrieved. Eleven studies were included in our systematic review. In the majority of studies (6 of 8), the ACE insertion/deletion (I/D) polymorphism did not differ between BD patients and controls. BD patients presented higher plasma renin activity in comparison with controls. The studies evaluating the RAS molecules in BD are very scarce and heterogeneous. The literature suggests a potential role of RAS in BD. Further studies are necessary to investigate this relationship.

Beta-adrenergic stimulation and antidepressant activity

The results presented here, together with the literature data, support the noradrenergic hypothesis of depressive states, and especially the involvement of beta-adrenergic receptors: --In animals, beta stimulants have the same spectrum of activity as other antidepressants. --These effects of both classical antidepressants and beta-adrenergic stimulants are antagonized by beta blockers. --Chronic administration of antidepressants results in a decrease of beta receptors. --Salbutamol, a beta-adrenergic stimulant had, in depressed patients, a clear and rapid antidepressant effect.