Parvalbumin‐immunoreactive cells in the olfactory bulb of the pigeon: Comparison with the rat

Abstract

The olfactory bulb (OB) shows special characteristics in its phylogenetic cortical structure and synaptic pattern. In the OB, gamma-aminobutyric acid (GABA), as an inhibitory neurotransmitter, is secreted from GABAergic neurons which contain parvalbumin (a calcium-binding protein). Many studies on the distribution of parvalbumin-immunoreactive neurons in the rodent OB have been published but poorly reported in the avian OB. Therefore, in this study, we compared the structure of the OB and distribution of parvalbumin-immunoreactive neurons in the OB between the rat and pigeon using cresyl violet staining and immunohistochemistry for parvalbumin, respectively. Fundamentally, the pigeon OB showed layers like those of the rat OB; however, some layers were not clear like in the rat OB. Parvalbumin-immunoreactive neurons in the pigeon OB were predominantly distributed in the external plexiform layer like that in the rat OB; however, the neurons did not have long processes like those in the rat. Furthermore, parvalbumin-immunoreactive fibres were abundant in some layers; this finding was not shown in the rat OB. In brief, parvalbuminimmunoreactive neurons were found like those in the rat OB; however, parvalbumin-immunoreactive fibres were significantly abundant in the pigeon OB compared to those in the rat OB. K E Y W O R D Sexternal plexiform layer, olfactory bulb, parvalbumin, pigeon, rat | 335 LEE Et aL.

Species Specific Structural Differences of the Main Olfactory Bulbs in Dog (Canis Familiaris) and Goat (Capra Hircus)

“…Therefore, species differences were observed in the GL, particularly the olfactory glomeruli structure is complex in animal with well-developed olfactory abilities, as described previously in elephant [29]. In contrast, species whose olfactory senses are mediocre developed, such as the domestic chicken (Gallus gallus), showed ordinary glomerular structure [34,35].…”

Current Stimulation of the Midbrain Nucleus in Pigeons for Avian Flight Control

“…Cryosection was prepared by sliding microtome (SM2010 R, Leica Biosystems, Nussloch, Germany) equipped with a freezing platform (BFS-40MP, Physitemp Instruments Inc., New Jersey, NJ, USA). Cresyl violet (CV) stain was done to examine the morphology of neural cells and the pattern of neuronal distribution, and the actual coordinates of the electrode insertion were determined by comparing the CV-stained section and an atlas of the pigeon brain [ 18 , 35 ].…”

“…Cryosection was prepared by sliding microtome (SM2010 R, Leica Biosystems, Nussloch, Germany) equipped with a freezing platform (BFS-40MP, Physitemp Instruments Inc., New Jersey, NJ, USA). Cresyl violet (CV) stain was done to examine the morphology of neural cells and the pattern of neuronal distribution, and the actual coordinates of the electrode insertion were determined by comparing the CV-stained section and an atlas of the pigeon brain [18,35]. Indoor walking, body turn, flapping or ultra-short range flying on electrical stimulation of the brain was evaluated in the multidisciplinary laboratory for animal experiments at the SNU veterinary hospital, and outdoor, short-range flying on electrical stimulation of the brain was evaluated in the aviary of the same hospital, the size of which is about 4 m in width, 15 m in length, and 3.5 m in height.…”