Investigaton of peripheral and central actions of angiotensin-(1-7) on urinary bladder regulation in Female Wistar rats

• Grant number: 18/00191-4
• Support type: Regular Research Grants
• Duration: June 01, 2018 - May 31, 2020
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal researcher: Monica Akemi Sato
• Grantee: Monica Akemi Sato
• Home Institution: Centro Universitário Saúde ABC. Fundação do ABC. Santo André , SP, Brazil

Abstract

The voiding dysfunctions affect men and women, as well as children around the world, with the highest percentage of cases occurring in women. These micturition dysfunctions can occur due to changes in detrusor muscle control, sphincter or both and may be due to injury or degeneration of the central and/or peripheral nervous system, as well as of peripheral organs. The maintenance of excretion and urinary storage depends on reflex mechanisms, and the onset of micturation is influenced by the Pontine Micturation Center (PMC), while urine storage is modulated by the Pontine Urine Storage Center (PUSC), which is found ventrolaterally to PMC. Studies on the injection of pseudorabies virus into the wall of the urinary bladder showed that, after a long period of incubation, infected neurons are found in the lumbosacral spinal cord, raphe nucleus, reticular formation, pontine micturition center (PMC), locus coeruleus, red nucleus, hypothalamus, preoptic area and cortical areas. These evidences indicate that a multisynaptic neuronal circuit is involved in the efferent control of the urinary bladder.The discovery of angiotensin- (1-7) (Ang 1-7) formed by an ACE-independent pathway, which was able to bind to the MAS receptor and have actions in vitro and in vivo, allowed its recognition as a biologically active peptide of the Renin-Angiotensin System.Using the immunofluorescence technique in the central nervous system of Wistar rats, the presence of the MAS receptor was demonstrated in areas related to the cardiovascular system in the medulla and also in the forebrain, as in the supraoptic nucleus and also in the lateral preoptic area. Although Ang- (1-7) actions have been demonstrated in some hypothalamic areas, there is still no evidence whether Ang 1-7 could act in prosencephalic areas such as the lateral preoptic area to modulate urinary bladder regulation.Thus, the present study will evaluate the hypothesis that Ang 1-7 could act in the lateral preoptic area to promote changes in urinary bladder control. In addition, it will be investigated whether Ang 1-7 could also act directly on the urinary bladder affecting its regulation. (AU)