Neurosteroid modulation of dendrodendritic inhibition in the mouse olfactory bulb.
The present report describes neurosteroid modulation of olfactory bulb function by examining the effects of intrabulbar infusion of dehydroepiandrosterone sulfate (DHEAS), a neurohormone discovered in rat brain, on field potentials in the granule cell layer evoked by paired-pulse stimulation of the mouse lateral olfactory tract. Infusion of DHEAS (5 nmol) significantly decreased the test response without affecting the conditioning response. As a consequence, DHEAS selectively potentiated paired-pulse depression, which is believed to be due to granule cell-mediated inhibition of the mitral/tufted cells. The granule-to-mitral/tufted dendrodendritic synapse is GABAergic. Taken together, these results suggest that DHEAS potentiates the GABAergic dendrodendritic inhibition exerted by the granule cells on the mitral/tufted cells.
Usui
M
M
Department of Veterinary Physiology, Veterinary Medical Science, Kagoshima University, Japan.
Kawasaki
Y
Y
Kaba
H
H
D000704:Analysis of Variance; D000818:Animals; D019314:Dehydroepiandrosterone Sulfate / Q000008:administration & dosage / Q000494:pharmacology*; D003712:Dendrites / Q000187:drug effects / Q000502:physiology*; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects*; D007263:Infusions, Parenteral; D051379:Mice; D008807:Mice, Inbred BALB C; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D009830:Olfactory Bulb / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D013569:Synapses / Q000187:drug effects / Q000502:physiology
D019314:Dehydroepiandrosterone Sulfate