Lobus Paraolfactorius


We found abundant alpha1 and gamma2 immunoreactivity throughout the chicken brain, mainly in the paleostriata and lobus paraolfactorius, dorsal thalamus and some nuclei of the brainstem.  

Therefore, the projections from these structures to the paleostriatum and the lobus paraolfactorius are amygdalostriatal, rather than corticostriatal connections..  

Conspicuously negative were the lobus paraolfactorius, including song nucleus area X, and the paleostriatum.  

By comparing our results of Metenkephalin immunoreactivity (Menkir) with the referred analogous ones of Substance P (SP) quoted in literature, we confirmed the strikingly similar labelling at the levels of the lobus paraolfactorius (LPO) and Paleostriatum augmentatum (PA), in contrast with the very low immunoreactivity at the Paleostriatum primitivum (PP) levels.  

Width and height measurements of each hemisphere were taken at eight locations, caudal to rostral, 400 microm apart starting at the level of the anterior commissure (CA) and ending at the lobus paraolfactorius (LPO).  

Although both ligands bound throughout the brain, most telencephalic regions, including the archistriatum, the neostriatum, and basal ganglia structures like lobus paraolfactorius, nucleus accumbens, and paleostriatum, showed a higher density of M1-like sites.  

VIP immunopositive structures were rarely associated with recognizable nuclei and they were observed in the organum septi laterale (LSO), the lobus paraolfactorius (LPO), the eminentia mediana (ME), the nucleus striae terminalis (nST) and the area ventralis of Tsai (AVT).  

Progesterone metabolism was then studied in five brain areas obtained by microdissection from the telencephalon (part of the lobus paraolfactorius immediately rostral to the preoptic area), the preoptic area, and the hypothalamus. The 5 beta-reduction of progesterone (production of 5 beta-DHP and 5 beta,3 alpha-ol) was very active but its 5 alpha-reduction (production of 5 alpha-DHP) was almost absent in the lobus paraolfactorius. Simultaneously, the experimental procedures induced significant decreases in the production of 5 beta-DHP by the lobus paraolfactorius, anterior, and medial hypothalamus but induced a significant increase in the production of this metabolite in the preoptic area.  

The highest densities of both D1 and D2 receptors were concentrated in the paleostriatum augmentatum, lobus paraolfactorius and olfactory tubercle.  

Sex differences were observed for norepinephrine in the sections containing the lobus paraolfactorius and the preoptic, anterior, and medial hypothalamus.  

In the telencephalon numerous DA axons were identified in the paleostriatum augmentatum and in the lobus paraolfactorius.  

Spontaneous and flash-altered multiunit activity MUA was recorded from the lobus paraolfactorius of young male quail reared in either long or short daily photoperiods.  

In the telencephalon, a number of SRIF-positive neurons was detected in the lobus paraolfactorius, hippocampus, and paleostriatum.  


-
[ View All ]