Contribution à l'étude de la transduction et du codage des informations olfactives. Etude éléctrophysiologique des variations du métabolisme minéral en réponse à la sollicitation du système olfactif.

Abstract : The results reported in this thesis were obtained by direct measurement of ion movements in the olfactory system using ion-selective microelectrodes. The investigations which were undertaken aimed to contribute to the studies on olfactory quality coding and to obtain additional insights on fluctuations in ionie metabolism underlying receptor depolarization and information processing in olfactory bulb glomeruli. Two Vertebrate species were used as study models. While olfactory bulb was studied in the rat, epithelial ion movements were investigated in the frog inasmuch as this animal allowed easier experimental approach. Utilizing the frog olfactory epithelium as a model structure, we first discovered that the stimulation-induced variations in extracellular K and Ca clearly show that Ca, unlike K, is directly involved in EOG generation. In the rat olfactory bulb, we focused on the metabolic aspects of odor quality coding. Olfactory nerve stimulation was found to induce a two-step increase in extracellular K - and decrease in Ca- within single glomeruli which were accompanied by a substantial fail in mitral cell firing rate. Extracellular K accumulation was viewed as a main mechanism by which the attenuation of glomerular transmission might occur. Some other original findings such as the lack of lateral spread of K and the higher tissue concentration of Na,K-ATPase activity in the glomerular layer, support this proposaI. Finally, the exploration of the ontogenie maturation of GABAergic inhibition in the rat olfactory bulb, showed that the former undergoes profound changes during the perinatal period. The main finding was that the olfactory bulb entry is dominated at birth by bicuculline-resistant GABAB receptors whereas typical GABAA receptors appear later. Our results are interpreted in relation with olfactory coding theories with special reference to attenuative processes occurring in olfactoty glomeruli.
Document type :
Theses
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-01748588
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 11:42:24 AM
Last modification on : Monday, April 16, 2018 - 10:40:19 AM
Long-term archiving on: Friday, September 14, 2018 - 1:48:59 AM

File

SCD_T_1990_0033_KHAYARI.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01748588, version 1

Collections

Citation

Abdelmajid Khayari. Contribution à l'étude de la transduction et du codage des informations olfactives. Etude éléctrophysiologique des variations du métabolisme minéral en réponse à la sollicitation du système olfactif.. Biologie animale. Université Henri Poincaré - Nancy 1, 1990. Français. ⟨NNT : 1990NAN10033⟩. ⟨tel-01748588⟩

Share

Metrics

Record views

32

Files downloads

36