Paraventricular nucleus

Glaucoma is characterized by the progressive degeneration of retinal ganglion cells (RGCs) and damage to the optic nerve, with increased intraocular pressure (IOP) being one of the risk factors for the development of the disease. In addition to their role in visual processing, RGCs project to the suprachiasmatic nucleus (SCN) in the hypothalamus, which is responsible for generating and synchronizing biological rhythms with the light-dark (LD) cycle. These rhythms include body temperature, locomotor activity, feeding behavior, and hormonal secretion patterns. We have demonstrated that animals in advanced stages of glaucoma show alterations in the rhythm of spontaneous locomotor activity and core body temperature. Furthermore, humans with glaucoma exhibit sleep disturbances and disruptions in the circadian rhythm of body temperature and blood cortisol levels. Considering that glucocorticoid secretion has an endogenous circadian profile mediated by the SCN, this study aims to evaluate the impact of glaucoma-induced rhythmic alterations on the hypothalamic-pituitary-adrenal (HPA) axis. For this purpose, we will use an animal model that spontaneously develops glaucoma, assessing the molecular components (gene and protein expression) of the HPA axis in glaucomatous (Dba/2j) and control (Dba/2j GPNMB+) animals.