Let it go: Depression facilitates disengagement from unattainable goals

BACKGROUND AND OBJECTIVES

Previous studies have demonstrated that clinging to unattainable goals is linked to the onset of depression. The present study investigated whether symptoms of a clinical depression are adaptive in that they facilitate disengagement from unattainable goals.

METHODS

A group of depressive inpatients (n = 40) was compared to a non-depressive control group (n = 38) in regard to how much time they spent on unsolvable anagrams, while controlling for group differences in the time spent on solvable anagrams.

RESULTS

In line with our hypothesis, depressive inpatients spent less time on unsolvable anagrams. There was no group difference in the time needed to solve the solvable anagrams.

LIMITATIONS

Our study tested disengagement from anagram tasks in the lab in a sample of depressive inpatients and thus may not be representative for contexts of disengagement from personal goals outside the lab or for people with milder or briefer forms of depression. Follow-up questions thus concern the development of goal disengagement processes in everyday life during the course of a major depressive episode.

CONCLUSIONS

Our findings provide evidence for the view that clinical depression, although pathological, might also serve an adaptive function. We discuss possible implications of our findings for psychotherapy.

Acetyl-coenzyme A deacylase activity in liver is not an artifact. Subcellular distribution and substrate specificity of acetyl-coenzyme A deacylase activities in rat liver

Whole liver and isolated liver mitochondria are able to release free acetate, especially under conditions of increased fatty acid oxidation. In the present paper it is shown that rat liver contains acetyl-CoA deacylase (EC 3.1.2.1) activity (0.72mumol/min per g wet wt. of liver at 30 degrees C and 0.5mm-acetyl-CoA). At 0.5mm-acetyl-CoA 73% of total enzyme activity was found in the mitochondria, 8% in the lysosomal fraction and 19% in the postmicrosomal supernatant. Mitochondrial subfractionation shows that mitochondrial acetyl-CoA deacylase activity is restricted to the matrix space. Mitochondrial acetyl-CoA deacylase showed almost no activity with either butyryl- or hexanoyl-CoA. Acetyl-CoA hydrolase activity from purified rat liver lysosomes exhibited a very low affinity for acetyl-CoA (apparent K(m)>15mm compared with an apparent K(m) value of 0.5mm for the mitochondrial enzyme) and reacted at about the same rate with acetyl-, n-butyryl- and hexanoyl-CoA. We could not confirm the findings of Costa & Snoswell [(1975) Biochem. J.152, 167-172] according to which mitochondrial acetyl-CoA deacylase was considered to be an artifact resulting from the combined actions of acetyl-CoA-l-carnitine acetyltransferase (EC 2.3.1.7) and acetylcarnitine hydrolase. The results are in line with the concept that free acetate released by the liver under physiological conditions stems from the intramitochondrial deacylation of acetyl-CoA.