Examinando por Autor "Nibaldo C. Inestrosa"

Mostrando 1 - 2 de 2
  • Miniatura
    Ítem
    Effects of enriched‑potassium diet on cardiorespiratory outcomes in experimental non‑ischemic chronic heart failure
    (2021) Karla G. Schwarz; Katherin V. Pereyra; Camilo Toledo; David C. Andrade; Hugo S. Díaz; Esteban Díaz‑Jara; Domiziana Ortolani; Angélica Rios‑Gallardo; Paulina Arias; Alexandra Las Heras; Ignacio Vera; Fernando C. Ortiz; Nibaldo C. Inestrosa; Carlos P. Vio; Rodrigo Del Rio
    Background: Chronic heart failure (CHF) is a global health problem. Increased sympathetic outflow, cardiac arrhythmogenesis and irregular breathing patterns have all been associated with poor outcomes in CHF. Several studies showed that activation of the renin-angiotensin system (RAS) play a key role in CHF pathophysiology. Interestingly, potassium (K+) supplemented diets showed promising results in normalizing RAS axis and autonomic dysfunction in vascular diseases, lowering cardiovascular risk. Whether subtle increases in dietary K+ consumption may exert similar effects in CHF has not been previously tested. Accordingly, we aimed to evaluate the effects of dietary K+ supplementation on cardiorespiratory alterations in rats with CHF. Methods: Adult male Sprague–Dawley rats underwent volume overload to induce non-ischemic CHF. Animals were randomly allocated to normal chow diet (CHF group) or supplemented K+ diet (CHF+K+ group) for 6 weeks. Cardiac arrhythmogenesis, sympathetic outflow, baroreflex sensitivity, breathing disorders, chemoreflex function, respiratory–cardiovascular coupling and cardiac function were evaluated. Results: Compared to normal chow diet, K+supplemented diet in CHF significantly reduced arrhythmia incidence (67.8 ± 15.1 vs. 31.0 ± 3.7 events/hour, CHF vs. CHF+K+), decreased cardiac sympathetic tone (ΔHR to propranolol:− 97.4 ± 9.4 vs. − 60.8 ± 8.3 bpm, CHF vs. CHF+K+), restored baroreflex function and attenuated irregular breathing patterns. Additionally, supplementation of the diet with K+ restores normal central respiratory chemoreflex drive and brogates pathological cardio-respiratory coupling in CHF rats being the outcome an improved cardiac function. Conclusion: Our findings support that dietary K+ supplementation in non-ischemic CHF alleviate cardiorespiratory dysfunction.
  • Miniatura
    Ítem
    Glutamatergic Receptor Trafficking and Delivery: Role of the Exocyst Complex
    (2020) Matías Lira; Rodrigo G. Mira; Francisco J. Carvajal; Pedro Zamorano; Nibaldo C. Inestrosa; Waldo Cerpa
    Cells comprise several intracellular membrane compartments that allow them to function properly. One of these functions is cargo movement, typically proteins and membranes within cells. These cargoes ride microtubules through vesicles from Golgi and recycling endosomes to the plasma membrane in order to be delivered and exocytosed. In neurons, synaptic functions employ this cargo tra cking to maintain inter-neuronal communication optimally. One of the complexes that oversee vesicle tra cking and tethering is the exocyst. The exocyst is a protein complex containing eight subunits first identified in yeast and then characterized in multicellular organisms. This complex is related to several cellular processes, including cellular growth, division, migration, and morphogenesis, among others. It has been associated with glutamatergic receptor tracking and tethering into the synapse, providing the molecular machinery to deliver receptor-containing vesicles into the plasma membrane in a constitutive manner. In this review, we discuss the evidence so far published regarding receptor tracking and the exocyst complex in both basal and stimulated levels, comparing constitutive tracking and long-term potentiation-related tracking.