Related Experiment Video

Updated: Sep 10, 2026

Multi-parameter Measurement of the Permeability Transition Pore Opening in Isolated Mouse Heart Mitochondria
13:42

Multi-parameter Measurement of the Permeability Transition Pore Opening in Isolated Mouse Heart Mitochondria

Published on: September 7, 2012

Cell-type-specific opening of the retinal ganglion cell mitochondrial permeability transition pore

Joshua P Vrabec1, Christopher J Lieven, Leonard A Levin

  • 1University of Wisconsin Medical School, Department of Ophthalmology and Visual Sciences, Madison, Wisconsin 53792-4673, USA.

Investigative Ophthalmology & Visual Science
|May 27, 2003
PubMed
Abstract

Insights

The mitochondrial permeability transition pore (PTP) in retinal ganglion cells (RGCs) opens abnormally, leading to cell death. This unique RGC PTP behavior may explain RGC susceptibility in certain mitochondrial diseases.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Mitochondrial Biology

Background:

  • Retinal ganglion cells (RGCs) are crucial for vision.
  • Apoptosis, or programmed cell death, is a key process in RGC survival and death.
  • The mitochondrial permeability transition pore (PTP) is implicated in cellular apoptosis.

Purpose of the Study:

  • To investigate the role of the mitochondrial permeability transition pore (PTP) in the apoptosis of axotomized retinal ganglion cells (RGCs) in vitro.
  • To understand the specific mechanisms of PTP involvement in RGC death.

Main Methods:

  • Primary rat retinal cultures with DiI-labeled RGCs were used.
  • Pharmacological agents modulating the PTP were applied.
  • Ratiometric imaging of mitochondrial membrane potential (DeltaPsi(m)) using JC-1 was performed.

Main Results:

  • PK11195 induced RGC death, unaffected by cyclosporin A (CsA).
  • The combination of CsA and PK11195 paradoxically caused massive RGC death and decreased DeltaPsi(m), indicating aberrant PTP regulation.
  • Mitochondrial depolarization led to ringlike body formation, distinct from other neuronal cells.

Conclusions:

  • Aberrant opening of the RGC PTP suggests unique structural or ligand interaction properties.
  • This unique PTP behavior may contribute to RGC vulnerability in mitochondrial diseases like Leber hereditary optic neuropathy.

More Related Videos

Immunohistochemical and Calcium Imaging Methods in Wholemount Rat Retina08:54

Immunohistochemical and Calcium Imaging Methods in Wholemount Rat Retina

Published on: October 13, 2014

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess07:35

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess

Published on: June 1, 2022

Related Concept Videos

The Retina01:32

The Retina

The retina is a layer of nervous tissue at the back of the eye that transduces light into neural signals. This process, called phototransduction, is carried out by rod and cone photoreceptor cells in the back of the retina.
Mitochondrial Membranes01:45

Mitochondrial Membranes

A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...
G-Protein Gated Ion Channels01:21

G-Protein Gated Ion Channels

GPCRs are primarily responsible for our sense of smell, taste, and vision.  The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Anatomy of the Eyeball01:20

Anatomy of the Eyeball

The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle layer, the vascular tunic,...
Photoreceptors and Visual Pathways01:22

Photoreceptors and Visual Pathways

At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category, whereas...