Patricio Orio

Simulación Molecular y Biología Computacionalpatricio-orio

Profesor Adjunto
Facultad de Ciencias, Universidad de Valparaíso

Doctor en Ciencias mención Biología Molecular, Celular y Neurociencias. Universidad de Chile (2004)
Director of Biophysics and Computational Biology PhD Program at University of Valparaíso

Curriculum Vitae

Contact Information:

E-Mail: patricio.orio at uv.cl
Teléfono: (56-32) 299 5538
Fax: (56-32) 250 8027
Dirección: Centro Interdisciplinario de Neurociencia de Valparaiso,
Pasaje Harrington 287. Valparaíso, Chile.

Mathematical Modelling of Neuron Behaviour

Neurons and neural networks show a complex behavior due to the high non-linearity of their responses to different stimuli. Much of what we currently understand about this behavior has come from the mathematical modeling of the different processes taking place in the cell membrane. The analysis of dynamical systems that arise from the physical and chemical principles underlying the transmission of electrical signals in living organisms has been a great aid in the understanding of experimental data, and is also a whole research field on its own.
My current field of work includes:

  • Modeling the activity and response of cold-sensitive nerve terminals. These nerve terminals have a spontaneous, rhythmic activity of action potential generation that appears to follow an ongoing sub-threshold oscillation of the membrane potential. This phenomenon is of interest as a model of intrinsic impulse pattern generation, as opposed to periodic pattern generation in networks with synaptic interactions. Previous models were focused on the oscillatory pattern generation, and they do not reproduce the dynamical response of cold-sensitive terminals to a cold stimulus. Moreover, they do not take into account mechanisms specifically modulated by cold, such as the recently cloned TRPM8 channel. It is of my interest to develop a model that includes the most prominent and recent experimental findings and that also resembles the dynamical behavior of the cold transduction phenomena. This work is part of Anillo de Ciencia y Tecnología ACT-1113 in collboration with Dr. Rodolfo Madrid and Dr. Bernardo Morales (USACH).
  • Modeling of the neural networks in the retina. In collaboration with Dr. Adrián Palacios, and as part of the ANR/CONICYT project KEOpS: Algorithms for modelling the visual system: From natural vision to numerical applications. My interest in this initiative is to develop and analyze conductance-based models of the Starburst Amacrine Cells network in the retina and their role in the direction selectivity of some ganglion cells.
  • Channel noise in neurons: Through  mathematical modeling and analysis, we want to understand the diverse effects that ion channel stochasticity has on neural excitability.

Selected Publications:

  • Olivares E, Salgado S, Maidana JP, Herrera G, Campos M, Madrid R and Orio P (2015). TRPM8-dependent dynamic response in a mathematical model of cold thermoreceptor. PLOS One 588(Pt 17):3141-8 doi: 10.1371/journal.pone.0139314
  • Pezo D, Soudry D and Orio P (2014) Diffusion approximation-based simulation of stochastic ion channels: which method to use? Front. Comput. Neurosci8:139. doi:10.3389/fncom.2014.00139
  • Escobar MJ, Pezo D, Orio P. (2013) Mathematical Analysis and Modeling of Motion Direction Selectivity in the Retina. J Physiol Paris 107(5):349-359. doi:10.1016/j.jphysparis.2013.08.003  
  • Boric K, Orio P, Viéville T, Whitlock K (2013) Quantitative Analysis of Cell Migration Using Optical Flow. PLoS ONE 8(7): e69574. doi:10.1371/journal.pone.0069574
  • Orio P., Parra A., Madrid R., González O., Belmonte C., Viana F. (2012) Role of Ih in the Firing Pattern of Mammalian Cold Thermoreceptors. J Neurophysiol 108:3009-3023 doi:10.1152/jn.01033.2011
  • Orio P. and Soudry D. (2012) Simple and Fast Implementation of the Diffusion Approximation Algorithm for Stochastic Ion Channels with Multiple States. PLoS ONE 7(5): e36670.
  • Latorre R., Brauchi S., Madrid R., Orio P. (2011) A Cool Channel in Cold Transduction. Physiology 26:273-285. 
  • Brauchi S., Orio P. (2011) Voltage Sensing in ThermoTRP Channels. Adv. Exp. Med. Biol. 704:517-530.
  • Orio P., Madrid R., de la Peña E., Parra A., Meseguer V., Bayliss D.A., Belmonte C., Viana F. (2009) Characteristics and physiological role of hyperpolarization-activated current Ih in mouse cold thermoreceptors. J Physiol 587:1961-1976.
  • González-Pérez V., Neely A., Tapia C., González-Gutiérrez G., Contreras G., Orio P., Lagos V., Rojas G., Estévez T., Stack K., Naranjo D. (2008) Slow inactivation in Shaker K channels is delayed by intracellular tetraethylammonium. J. Gen. Physiol. 132:633-50.
  • Orio P., Torres Y., Rojas P., Carvacho I., Garcia M.L., Toro L., Valverde M.A., Latorre R. (2006). Structural Determinants for Functional Coupling Between the β and α Subunits in the Ca2+-activated K+ (BK) Channel. J. Gen. Physiol. 127:191-204.
  • Orio, P., Latorre, R. (2005) Differential effect of β1 and β2 subunits on BK Channel Activity. J. Gen. Physiol. 125:395-411.
  • Brauchi, S., Orio, P., Latorre, R. (2004) Clues to understanding cold sensation. Thermodynamics and electrophysiological analysis of the cold receptor TRPM8. Proc Natl Acad Sci USA. 101:15494-15499
  • Orio, P., Rojas, P., Ferreira, G. and Latorre, R. (2002) New Disguises for an Old Channel: MaxiK Channel β subunits. News Physiol. Sci. 17:156-161.
  • Valverde, M.A.; Rojas, P.; Amigo, J.; Cosmelli, D.; Orio, P.; Bahamonde, M.I.; Mann, G.E.; Vergara, C. and Latorre, R. (1999). Acute Activation of Maxi-K Channels (hSlo) by Estradiol Binding to the β Subunit. Science 285:1929-1931.