Biology subjects

ORTIZ-LEAL, I.

Publications and source records attributed to ORTIZ-LEAL, I..

3 recordsLinked to original sources

bioRxiv2025

Development of the Olfactory and Vomeronasal Systems in the Fossorial Water Vole (Arvicola scherman). I. The Late Prenatal Stages

Chemical communication is essential for mammalian survival from the earliest stages of life, yet most of what is known about the prenatal development of the olfactory and vomeronasal systems comes from laboratory rodents. These models, while invaluable, may not fully represent the developmental trajectories of wild species living under natural ecological pressures. Here we investigated the fetal development of the nasal chemosensory systems in the fossorial water vole (Arvicola scherman), a free-living arvicoline rodent with a highly subterranean lifestyle. We analyzed fetuses at embryonic days E17 and E21 (term) using classical histology, immunohistochemistry (markers: Gi2, Go, G{gamma}8, CB, CR, PGP 9.5, GAP-43, {beta}-tubulin, MAP2), and lectin histochemistry (UEA, LEA, SBA, STA, DBA). This combined approach enabled us to assess structural maturation, neuronal differentiation, and the temporal dynamics of glycoconjugate expression in the vomeronasal organ (VNO), olfactory epithelium (OE), and the main (MOB) and accessory olfactory bulbs (AOB). By E21, the MOB displayed a six-layered adult-like organization with well-defined glomeruli and interneuronal populations, whereas the AOB showed delayed morphological maturation but already exhibited selective molecular signatures in its nerve and superficial layers. Prenatally, the VNO underwent conspicuous structural differentiation, including stratification of the sensory epithelium, robust axonal fasciculation, and early development of vomeronasal glands. Immunohistochemical analysis revealed early expression of G-protein subunits and calcium-binding proteins, indicating premature pathway specification and interneuronal circuit formation. Lectin labeling provided additional insights: SBA emerged as a highly selective marker of the vomeronasal pathway; UEA highlighted early compartmentalization of vomeronasal projections; LEA showed a conserved, pan-chemosensory binding pattern across systems; and DBA, despite its lower specificity, revealed late-onset reactivity in postmitotic neurons. Together, these findings demonstrate that A. scherman exhibits a remarkably accelerated prenatal maturation of its chemosensory systems compared with laboratory rodents. This early functional readiness likely reflects adaptive pressures of a fossorial lifestyle, emphasizing the importance of incorporating wild species into developmental neurobiology to refine our understanding of mammalian chemosensory evolution.

neuroscience↗

bioRxiv2023

Sensory Adaptations: Insights into the Vomeronasal System of the Iberian Wolf

Wolves, like other canids, extensively use chemical signals for various aspects of communication, including territory maintenance, reproductive synchronization, and social hierarchy signaling. Pheromone-mediated chemical communication operates unconsciously among individuals, acting as a mysterious sixth sense that regulates both their physiology and behavior. Despite their crucial role in the life of the wolf, there is a surprising lack of comprehensive research on the neuroanatomical and physiological bases of chemical communication in wolves. This study delves into the Iberian wolf vomeronasal system (VNS) and examines potential changes brought about by dog domestication. Our findings show that the Iberian wolf possesses a fully functional VNS vital for pheromone-mediated communication. While macroscopic similarities between the wolf and domestic dog VNS are observed, there are notable microscopic differences. These include the presence of neuronal clusters associated with the sensory epithelium of the vomeronasal organ (VNO) and a higher differentiation degree of the accessory olfactory bulb (AOB). Immunohistochemical markers reveal the expression of the two main families of vomeronasal receptors (V1R and V2R) in the VNO. However, only the V1R family is expressed in the AOB. These findings not only provide deep insights into the VNS of the wolf but also hint at how domestication might have altered neural configurations that underpin species-specific behaviors. This understanding has implications for innovative strategies, such as employing semiochemicals for wolf population management, aligning with modern conservation goals.

neuroscience↗

bioRxiv2022

FIRST INSIGHTS IN A NON-RODENT MODEL SPECIES OF THE OLFACTORY LIMBUS. THE RED FOX (Vulpes vulpes) AS A CASE IN POINT

The mammalian olfactory systems can be divided into several subsystems based on the anatomical location of their neuroreceptor cells and the family of receptors they express. The more in depth studied systems are the main olfactory system and the vomeronasal system, whose first integrative enters are the main and the accessory olfactory bulb, respectively. In addition, there is a range of olfactory subsystems which converge to the transition zone located between the main olfactory bulb and the accessory olfactory bulb., which has been termed as olfactory limbus (OL) and includes specialized glomeruli which receive uncanonical sensory afferences and interact with the MOB and AOB. Beyond the laboratory rodents, there is a lack of information regarding the olfactory subsystems of carnivores. We have focused on the specific study of the olfactory limbus of the fox, performing serial histological sections, general and specific histological stainings, including both double and simple immunohistochemical and lectin-histochemical labeling techniques. As a result, we have been able to determine that the OL of the fox shows an uncommon development with a high degree of development and complexity. This makes this species a novel mammalian model that could provide a wider understanding of non-canonical pathways involved in the processing of chemosensory cues.

neuroscience↗