Morphoquantitative assessment of Spinal cord anterior horn of Callithrix Jacchus em different gender and ages.
Spinal cord, Motor neurons, Aging
The spinal cord is one of the most important neural centers, among its main functions is to promote locomotion, one of the most complex and important capabilities developed by animals, including humans. The nerves that depart from it send information from the central nervous system (CNS) to the muscles and glands, creating movement according to the brain's command. It is scientifically proved that with advancing age this motor function is completely affected. Nevertheless, little is known about the possible morphochemical alterations related to motor neuron aging, especially in marmosets, and whether there are distinct responses to gender-related aging.The data related to studies associated with spinal cord quantification are still controversial, since most of them use two-dimensional counting methods, being the main innovation of this work the 3D approach of the possible morphoquantitative changes. This research aimed to investigate the possible morphochemical differences of the spinal cord, using stereological delineation techniques during senescence in different genders (males and females). For this, it were used used 18 marmosets (Callithrix jacchus), which were divided into 6 groups according to their age groups and genders: young male group (n = 4), male adult group (n = 4), male elderly group (n = 2), female young group (n = 4), female adult group (n = 3) and female elderly group (n = 1). After euthanasia all animals were perfused with formalin solution (4%) in PBS, then the spinal cord was removed, weighed, measured, sectioned on the cryostat (being systematically, uniformly and randomly sampled), mounted on slides and stained using the Nissil protocol. Stereological analyzes were performed later, with the application of the Cavaliere and Delesse principles, the volume of the substances (white and gray), the anterior horn and the neuronal volume density of the horn of interest were estimated. Preliminary analysis showed that there was a reduction in the gray matter reference volume in females during aging, as well a reduction was registered related to the anterior horn regardless of gender. Regarding neuronal density, a reduction was observed during the maturation process in males.