BIO 3153 Lecture Notes - Lecture 16: Ion Channel, Electrochemical Gradient, Intracellular Ph

• School: University of Ottawa
• Department: Biology
• Course: BIO 3153
• Professor: Michael Jonz

Document Summary

Ion channels exhibit a hydrophilic pore and may be gated. Voltage-gated channels: opening occurs following a change in membrane potential (depolarization or hyperpolarization: k+, na+, ca2+ channels, subtypes that are sensitive to changes in voltage, 2. Ligand-gated (extracellular): opening occurs because of binding of an extracellular ligand (neurotransmitters, glutamate, ach: common in the peripheral nervous system, receptors that receive neurotransmitters being received across the synapse, 3. Ligand-gated (intracellular): channel gating is regulated by binding of an intracellular factor (atp, camp) k+, cyclic nucleotide-gated (cng) channels: binds to the inside (cytosolic, 4. Mechanically-gated: a mechanical stress or force opens the channel: cation channels in stereocilia of hair cells, stress or force opens up the channel. Na+ channels of neurons: na+ channels move from a closed, to an open, to an inactivated state. Experiment: recording movement of na+ and k+, changes in membrane potential, 1. A brief stimulus is given to a neuron: 2. Na+ channels open and cell depolarizes: 3.