Stress-induced depression

Can stress cause depression? This was the key question posed in this discourse. An affirmative answer, it was stated, cannot rest on clinical and epidemiological grounds alone but requires data indicating that stress may inflict neuronal disturbances similar to those that have been observed in (subtypes of) depression and presumably play a role in their pathophysiology. The answer to that key question is cautiously and tentatively confirmatory. The argument is as follows.

MA ergic disturbances may occur in depression (Chapter 7). They seem not to be linked to a particular diagnostic category or to a particular syndrome, but rather to some syndromal components. Lowering of 5-HT metabolism and downregulation of the 5-HT1A receptor system seem to be associated with disruption of regulation of anxiety and aggression. Anxiety may be further enhanced by hyperfunction of the 5-HT2 receptor system, either directly or indirectly as a consequence of downregulation of the 5-HT1A receptor system. The NA-system can be likewise out of balance. Both signs of hypo- and hyperfunction have been reported, possibly stage-related: hyperfunction linked to anxiety and hyperarousal in the early phases, and NA ergic deficits developing later on accompanied, on a behavioural level, by fatigue and inertia.

DA metabolism has been found to be lowered in some depressed patients. Motor retardation and anhedonia are the likely behavioural correlates.