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This study aims to quantify the relative effects of density-dependent (feedback structure) and density-independent climatic factors (rainfall) in regulating the short-term population dynamics of wood mice Apodemus sylvaticus Linnaeus, 1758 in three Mediterranean forest plots. Rainfall and density explained additively 62% of variation in population growth rates (38 and 24%, respectively), with no differences among study plots. Population growth rate was positive during autumn–winter and negative during spring–summer during a 2.5-year period. Population rate of change was negatively affected by wood mouse density during the normal breeding season of Mediterranean mice (autumn–winter) but not outside it. Growth rate was positively affected by the cumulative amount of rainfall three months before the normal breeding season, but not during it. Female breeding activity and recruitment did not differ among plots, and was not affected by density or rainfall. However, recruitment was positively affected by density and, marginally, by rainfall. Our results suggest that intraspecific competition (density-dependence) and food availability (rainfall) are equally important factors driving wood mouse population dynamics in Mediterranean forests. Mechanisms underlying density-dependence during the breeding season seemed to be based on food-mediated survival rather than on behaviourally-mediated reproduction. Taken together, these results indicate a high sensitivity of marginal Mediterranean wood mouse populations to the expected climate changes in the Mediterranean region.
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Neuropeptides in neurogenic disorders of the cardiovascular control

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Growing number of studies reveal that the brain neural network plays significant role in the short-term and long-term regulation of the cardiovascular functions. The neurons involved in the complex neurogenic control of the cardiovascular system use classical neurotransmitters and nonconventional mediators such as peptides (angiotensin II, vasopressin, natriuretic peptides, endothelins, opioids, cytokines), steroids, ouabaine-like factors and gaseous compounds. Among them the neuropeptides form a group of substances arising significant interest. Thanks to wide distribution of peptidergic neurons in the central nervous system, location of peptide receptors on neurons and glial cells, versatile but frequently overlapping mechanisms of activation of the intracellular processes the neuropeptides play significant role in short-term and long-term regulation of excitability and remodeling of the neurons. In several instances they modulate effects of the classical transmitting systems involved in regulation blood pressure, heart rate, water-electrolyte balance, metabolism, stress, pain, mood and memory. Prolonged activation or inhibition of specific neuropeptide pathways frequently results in long-lasting disorders of several regulatory systems. In this review this is exemplified by overactivity of angiotensin II, vasopressin and cytokines in the brain during hypertension, heart failure and stress. Multifarious actions of angiotensin II and vasopressin, and their mutual interaction with cytokines make of these neuropeptides excellent candidates for the compounds responsible for long-term resetting of the central cardiovascular control, and forming a link between the cardiovascular diseases, stress and mood disorders.
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