Histological features and Gα_olf expression patterns in the nasal cavity of sea turtles

Abstract

Sea turtles use olfaction to detect volatile and water‐soluble substances. The nasal cavity of green turtles (Chelonia mydas) comprises morphologically defined the anterodorsal, anteroventral, and posterodorsal diverticula, as well as a single posteroventral fossa. Here, we detailed the histological features of the nasal cavity of a mature female green turtle. The posterodorsal diverticulum contained spongy‐like venous sinuses and a wave‐shaped sensory epithelium that favored ventilation. Secretory structures that were significant in sensory and non‐sensory epithelia were probably involved in protection against seawater. These findings suggested that green turtles efficiently intake airborne substances and dissolve water‐soluble substances in mucous, while suppressing the effects of salts. In addition, positive staining of Gαs/olf that couples with olfactory, but not vomeronasal, receptors was predominant in all three types of sensory epithelium in the nasal cavity. Both of airborne and water‐soluble odorants seemed to be detected in cells expressing Gαolf and olfactory receptors.

Pheromone Sensing in Mammals: A Review of the Vomeronasal System

“…It consists of a set of anatomically and histologically distinguishable structures from the main olfactory system. It is present in most reptiles [165,166] and amphibians [167], but it is particularly developed in mammals, in which this chemosensory system comprises three main components: the vomeronasal organ (VNO) (Figure 6), which acts as the peripheral chemoreceptor organ detecting chemical signals; the vomeronasal nerve, transmitting information to the brain; and the accessory olfactory bulb (AOB), the first neural center where vomeronasal afferent information is processed and integrated before heading to specific areas of the CNS [168].…”

Pheromone Sensing in Mammals: A Review on the Vomeronasal System

“…It consists of a set of anatomically and histologically distinguishable structures from the main olfactory system. It is present in most reptiles [165,166] and amphibians [167], but it is particularly developed in mammals, in which this chemosensory system comprises three main components: the vomeronasal organ (VNO) (Figure 6), which acts as the peripheral chemoreceptor organ detecting chemical signals; the vomeronasal nerve, transmitting information to the brain; and the accessory olfactory bulb (AOB), the first neural center where vomeronasal afferent information is processed and integrated before heading to specific areas of the CNS [168]. The significant functional diversity of the vomeronasal system is expressed in the existence of three distinct subpopulations of vomeronasal sensory neurons.…”