The calculated values of the binding energy of nonapeptides with receptors in docking with their influence on reabsorption of osmotically free water in a rat bud in vivo were compared. Vasotocin and some its analogs were intramuscularly introduced to non-narcotized rat females of the Wistar line in doses from 0.1 pmol to 0.5 nmol/kg of body weight against the background of peroral water load (50 ml/kg of body weight). A significant correlation between the calculated interaction energy of peptides with V2-receptors and an increase of reabsorption of osmotically free water in the rat bud stimulated by injection of nonapeptides was found. The results evidence that alterations in rat bud in vivo caused by analogs of vasotocin and their interactions with V2-receptors can be accurately simulated.
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J Comp Physiol B
January 2025
Departamento de Fisiologia, Instituto de Biociências da Universidade de São Paulo, São Paulo, Brazil.
During the transition from fresh waters to terrestrial habitats, significant adaptive changes occurred in kidney function of vertebrates to cope with varying osmotic challenges. We investigated the mechanisms driving water conservation in the mammalian nephron, focusing on the relative contributions of active ion transport and Starling forces. We constructed a thermodynamic model to estimate the entropy generation associated with different processes within the nephron, and analyzed their relative importance in urine formation.
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Department of Biosciences, Biotechnologies and Environment, University of Bari "Aldo Moro", 70125 Bari, Italy.
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J Exp Biol
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View Article and Find Full Text PDFAm J Physiol Renal Physiol
December 2024
Tulane Hypertension and Renal Center of Excellence and Department of Physiology, Tulane University School of Medicine, New Orleans, Louisiana, United States.
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