title: Alpha-1 adrenergic receptors gate rapid orientation-specific reduction in visual discrimination.
abstract: Prolonged imbalance in sensory experience leads to dramatic readjustments in cortical representation. Neuromodulatory systems play a critical role in habilitating experience-induced plasticity and regulate memory processes in vivo. Here, we show that a brief period of intense patterned visual stimulation combined with systemic activation of alpha-1 adrenergic neuromodulator receptors (α(1)-ARs) leads to a rapid, reversible, and NMDAR-dependent depression of AMPAR-mediated transmission from ascending inputs to layer II/III pyramidal cells in the visual cortex of young and adult mice. The magnitude of this form of α(1)-AR long-term depression (LTD), measured ex vivo with miniature EPSC recordings, is graded by the number of orientations used during visual experience. Moreover, behavioral tests of visual function following the induction of α(1)-AR LTD reveal that discrimination accuracy of sinusoidal drifting gratings is selectively reduced at high spatial frequencies in a reversible, orientation-specific, and NMDAR-dependent manner. Thus, α(1)-ARs enable rapid cortical synaptic depression which correlates with an orientation-specific decrease in visual discrimination. These findings contribute to our understanding of how adrenergic receptors interact with neuronal networks in response to changes in active sensory experience to produce adaptive behavior.
authors: Department of Molecular Neurobiology, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany. mariomtv@hotmail.com
authors: Mario
authors: M
authors: Treviño
authors: Sebastian
authors: S
authors: Frey
authors: Georg
authors: G
authors: Köhr
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000494:pharmacology; D000375:Aging / Q000523:psychology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004192:Discrimination, Psychological / Q000187:drug effects / Q000502:physiology*; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009949:Orientation / Q000187:drug effects / Q000502:physiology*; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000187:drug effects; D017966:Pyramidal Cells / Q000502:physiology; D018091:Receptors, AMPA / Q000502:physiology; D018340:Receptors, Adrenergic, alpha-1 / Q000187:drug effects / Q000502:physiology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology; D014792:Visual Acuity / Q000187:drug effects / Q000502:physiology; D014793:Visual Cortex / Q000187:drug effects / Q000502:physiology; D014796:Visual Perception / Q000187:drug effects / Q000502:physiology*
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D018091:Receptors, AMPA; D018340:Receptors, Adrenergic, alpha-1