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Stressful events experienced during early life are associated with increased vulnerability of developing psychopathology in adulthood. In the present study, we exposed 9-day-old Wistar rats to 24 h maternal deprivation (MD) with the aim to investigate the impact of early life stress (ELS) on morphological, biochemical, and functional aspects of the prefrontal cortex (PFC), a brain region particularly sensitive to stress. We found that in the superficial medial orbital cortex (MO), young adult male rats had reduced density of GAD67 and CCK immunopositive cells, while the rostral part of the ventral lateral orbital cortex (roVLO) showed a decrease in the density of GAD67 immunopositive cells in both superficial and deep layers. In addition, the superficial rostral part of area 1 of the cingulate cortex (roCg1) and deep prelimbic cortex (PrL) was also affected by MD indicated by the reduction in PV immunopositive cellular density. Furthermore, MD induced upregulation of brain-derived neurotrophic factor (BDNF), while it did not affect the overall expression of Iba1 in neonatal or young adult PFC as measured by Western blot, however, microglial activation in young adult MD rats was detected immunohistochemically in deep layers of MO and infralimbic cortex (IL). Interestingly, when young adult male rats were subjected to a behavioral flexibility test in a T-maze, MD rats showed a subtle impairment in T-maze reversal learning indicating a mildly affected PFC function. Taken together, our findings demonstrated that MD reduced the density of interneurons and induced microglial activation, in particular, PFC areas at young adulthood, and could alter synaptic plasticity accompanied by PFC dysfunction.

Early life stress has profound effects on the development of the central nervous system. We exposed 9-day-old rat pups to a 24 h maternal deprivation (MD) and sacrificed them as young adults (60-day-old), with the aim to study the effects of early stress on forebrain circuitry. We estimated numbers of various immunohistochemically defined interneuron subpopulations in several neocortical regions and in the hippocampus. MD rats showed reduced numbers of parvalbumin-expressing interneurons in the CA\(_1\) region of the hippocampus and in the prefrontal cortex, compared with controls. Numbers of reelin-expressing and calretinin-expressing interneurons were also reduced in the CA1 and CA\(_3\) hippocampal areas, but unaltered in the neocortex of MD rats. The number of calbinin-expressing interneurons in the neocortex was similar in the MD rats compared with controls. We analyzed cell death in 15-day-old rats after MD and found no difference compared to control rats. Thus, our results more likely reflect the downregulation of markers than the actual loss of interneurons. To investigate synaptic activity in the hippocampus we immunostained for glutamatergic and inhibitory vesicular transporters. The number of inhibitory synapses was decreased in the CA\(_1\) and CA\(_3\) regions of the hippocampus in MD rats, with the normal number of excitatory synapses. Our results indicate complex, cell type-specific, and region-specific alterations in the inhibitory circuitry induced by maternal deprivation. Such alterations may underlie symptoms of MD at the behavioral level and possibly contribute to mechanisms by which early life stress causes neuropsychiatric disorders, such as schizophrenia.

Early life adversities leave long-lasting structural and functional consequences on the brain, which may persist later in life. Dopamine is a neurotransmitter that is extremely important in mood and motor control. The aim of this study was to investigate the effect of maternal deprivation during the ninth postnatal day on the volume of dopaminergic nuclei and the number of dopaminergic neurons in adolescence and adulthood. Maternally deprived and control Wistar rats were sacrificed on postnatal day 35 or 60, and the dopaminergic neurons were stained in coronal histological sections of ventral midbrain with the tyrosine hydroxylase antibody. The volume of dopaminergic nuclei and the number of dopaminergic neurons in the substantia nigra (SN) and ventral tegmental area (VTA) were analyzed in three representative coordinates. Maternal deprivation caused weight loss on postnatal day 21 (weaning) and corticosterone blood level elevation on postnatal days 35 and 60 in stressed compared to control rats. In maternally deprived animals, the volumes of SN and VTA were increased compared to the controls. This increase was accompanied by an elevation in the number of dopaminergic neurons in both nuclei. Altogether, based on somatic and corticosterone level measurements, maternal deprivation represents a substantial adversity, and the phenotype it causes in adulthood includes increased volume of the dopaminergic nuclei and number of dopaminergic neurons.

Stachyoideae; fatty acids; chemotaxonomy. Abstract--Fatty acid composition of nutlet lipids in 28 species from the Stachyoideae, subfamily of the Lamiaceae, have been surveyed. In all species, octadecadienoic acid (18:2) was dominant. Octadecatrienoic acid (18:3) was a minor constituent in most species, except Physostegia virginiana and Lamium spp. The 18:3/18:2 ratio in Physostegia and Lamium ranged from 0.62 to 1.05. This ratio in all other species was signifi- cantly smaller (-0.25). Taxonomic value and phylogenetic implications of results are discussed.

Fatty acid composition of nutlet lipids in 62 species from the Saturejoideae, seven species from the Ajugoideae and four species from the Scutellarioideae have been analysed. Linolenate was the predominant acid in all species from the Saturejoideae but in the Ajugoideae, linoleate and linolenate were the major fatty acids. In the Scutellarioideae, linoleate was the dominant fatty acid. Results showed that the fatty acid composition of nutlet lipids and their linolenate/linoleate ratios may be useful as taxonomic markers for the differentiation of genera belonging to different subfamilies of the Lamiaceae.

Fatty acids were analysed in the seeds of 40 species from 12 genera of the Papaveraceae and 14 species from four genera of the Fumariaceae. Linoleate was predominant in both families; however, its content was 11% greater on average in the Papaveraceae. With Papaver orientale and Corydalis cava intraspecific variability of fatty acid patterns of seed lipids was studied; no large differences between samples were encountered. Triacylglycerols were the dominant lipid class. Members of Papaveraceae show a higher triacylglycerol but lower free fatty acid content than members of Fumariaceae.

Analyses of fatty acids of seed lipids in five species of Mentha from different localities in Serbia are reported.