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Treatment with monocrotaline causes pulmonary hypertension in rats. This results in severe pressure overload-induced hypertrophy of the right ventricles, whilst the normally loaded left ventricles do not hypertrophy. Both ventricles are affected by enhanced neuroendocrine stimulation in this model. We analyzed in this model load-induced and catecholamine-induced changes of right and left ventricular proteome by two-dimensional gel electrophoresis, tryptic in-gel digest, and matrix-assisted laser desorption/ionization-time of flight mass spectrometry. All analyzed animals showed right ventricular hypertrophy without signs of heart failure. Changes of 27 proteins in the right and 21 proteins in the left ventricular myocardium were found. Given the hemodynamic features of this animal model, proteome changes restricted to the right ventricle are caused by pressure overload. We describe for the first time a potentially novel pathway (BRAP2/BRCA1) that is involved in myocardial hypertrophy. Furthermore, we demonstrate that increased afterload-induced hypertrophy leads to striking changes in the energy metabolism with down-regulation of pyruvate dehydrogenase (subunit beta E1), isocitrate dehydrogenase, succinyl coenzyme A ligase, NADH dehydrogenase, ubiquinol-cytochrome C reductase, and propionyl coenzyme A carboxylase. These changes go in parallel with alterations of the thin filament proteome (troponin T, tropomyosin), probably associated with Ca(2+) sensitization of the myofilaments. In contrast, neurohumoral stimulation of the left ventricle increases the abundance of proteins relevant for energy metabolism. This study represents the first in-depth analysis of global proteome alterations in a controlled animal model of pressure overload-induced myocardial hypertrophy.

Hand use was compared in 45 individuals of three genera of the Callitrichinae (Callithrix, Saguinus, Leontopithecus) which differ concerning their postural and manipulative behaviour. The Postural Origins theory of MacNeilage et al. (1987) predicts left-hand preference for visually guided reaching, especially when performed from a vertical clinging posture (as mainly seen in Callithrix) and right-hand preference for manipulative acts (as shown by Leontopithecus). Five tasks were carried out, differing in sensory modality (visual/tactile), postural requirements (vertical/quadrupedal) and task demands (accessibility to food-items). Data on successful left and right-hand reaching and mouth pick-ups were collected using all occurrences sampling. Statistical analysis comprised calculation of binominal z-score, application of unbalanced repeated measures models with structured covariance matrices and analysis of covariance. All individuals displayed hand preferences not influenced by task design. The genera differed in the hand preferred: Leontopithecus showed a greater proportion of right-hand preferences, whereas Callithrix tended to prefer the left hand. Saguinus was intermediate between these two genera. The results point out that genus-specific foraging strategies determine population-level hand preferences rather than task-specific demands. The differences in foraging strategy and hand preference among the three genera correspond to the Postural Origins theory (MacNeilage et al., 1987). When feeding on freely accessible, non-mobile food items, most individuals showed a clear preference in picking-up with the mouth or with one hand. Callithrix took objects predominantly with the mouth, Leontopithecus preferred the hand and Saguinus favoured neither mouth nor hand. Mouth-hand preferences can also be linked to genera differences on hand function in foraging behaviour.