One hundred and fifty-nine women were measured for depressive and anxiety symptoms from late pregnancy through to 12 months postpartum. Partial correlations revealed stability of depressive and anxiety symptoms across time. Depressive symptoms did not predict anxiety at any time point. Anxiety predicted increases in depressive symptoms from late pregnancy to early postpartum, but not from early postpartum to mid postpartum. Anxiety predicted depressive symptoms from mid postpartum to late postpartum, however, not when social support in late pregnancy was controlled for.

1. The inhibitory effect of t-butyl hydroperoxide on 0 2 uptake by perfused rat liver and by isolated hepatocytes was investigated with isolated mitochondria.2 . 0 2 uptake by mitochondria oxidizing the ketoacids, 2-oxoglutarate and pyruvate, was substantially decreased upon addition of t-butyl hydroperoxide, that of isocitrate was only slightly decreased, and that of succinate and of 3-hydroxybutyrate was practically unchanged. The reduction product of the hydroperoxide, t-butyl alcohol, showed no effect. The inhibitory effect of the hydroperoxide was reversed upon addition of dithioerythritol, a thiol reductant. The inhibitory effect of the hydroperoxide was mimicked by the penetrant disulfide, cystamine, and by the thiol-oxidizing agent, diamide.3. Mitochondrial extracts from rats fed a selenium-deficient diet were shown to have virtually no measurable GSH peroxidase activity. The hydroperoxide had almost no inhibitory effect on 2-oxoglutarate-dependent 0 2 uptake in mitochondria from selenium-deficient rats.4. These observations demonstrate effects of GSH peroxidase activity in the mitochondrial matrix on the pattern of substrate oxidations, possibly with the ketoacid oxidases, dependent on coenzyme A and lipoamide, as main target sites. In view of the known steady-state formation of mitochondrial 0 2 and H202, a connection between the resulting oxidation of mitochondrial GSH and NADPH and the regulation of mitochondrial substrate oxidations is proposed.The concept of the physiological occurrence of hydrogen peroxide and organic hydroperoxides in mammalian tissues has received experimental support in recent years (cf. review in [l, 1 a]). The mitochondrial generation of H202 has been demonstrated by Chance and his colleagues [2 -41, and subcellular distribution studies by Flohe and Schlegel [5] revealed the presence of GSH peroxidase and GSSG reductase in the mitochondrial matrix space, with catalase activity being quite low [5,6]. A continuous flow of reducing equivalents through the mitochondrial 2 GSH/GSSG redox system, ultimately expressed as a utilization of NADPH, must be considered to take place under aerobic conditions [7,8]. It is therefore of interest to investigate the effects of hydroperoxides on mitochondrial metabolism.When introducing externally added hydroperoxides, e.g. t-butyl hydroperoxide or cumene hydroperoxide, for steady-state perturbation of the intracellular glutathione system, we observed a reversible decrease of 0 2 uptake by the isolated perfused rat liver [7,9]. The nature of this effect is analysed in the Trivial Name. Diamide, diazenedicarboxylic acid bis(N,N-dimethy lamide) . present paper using isolated hepatocytes and isolated mitochondria.Jocelyn [lo] has found that GSH is indeed oxidised in the presence of t-butyl hydroperoxide in isolated rat liver mitochondria. Thus, the present investigation was directed to contribute to an understanding of the possible relationships betwen the formation of hydroperoxides and the effects of disulfides on mitochondrial oxidations which...

1. The component reactions of the purine nucleotide cycle were studied in cytosol extracts of rat liver. 2. AMP deaminase was strongly activated by ATP and analogues of ATP. 3. IMP was converted into ATP by a system requiring the presence of aspartate, GTP and a nucleoside triphosphate-regenerating system. 4. Under appropriate conditions, NH3 was produced from aspartate. 5. From the rates at which these reactions occur it is concluded that the purine nucleotide cycle may have sufficient activity to be a major pathway of amino acid deamination in liver.

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