Effects of the nicotine exposure on puberty onset and regularity of the estrous cycle of albino rats exposed during the intrauterine and lactation phases

• Grant number: 19/09043-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2019
• End date: July 31, 2020
• Field of knowledge: Biological Sciences - Morphology - Embryology
• Principal Investigator: Camila Cicconi Paccola
• Grantee: Jaqueline Castelani de Souza
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Smoking is one of the main causes of preventable death in the world and has a great impact on the health of smokers, including on reproduction. Studies point to changes in fertility of the offspring exposed to nicotine, the main component of cigarette smoking, during pre and postnatal development, such as irregular menstrual/estrous cycles and alteration in onset of puberty. However, the existing data are conflicting in relation to anticipation or delay of puberty, which highlights the importance of this project. Therefore, this work aims to verify the effects of exposure to nicotine during the intrauterine and lactation phases on the establishment of puberty and regularity of the estrous cycle of albino rats. For this, the pregnant rats will receive an osmotic pump containing nicotine (2mg/kg/day) from the first day of pregnancy, in order to expose the offspring throughout pregnancy and lactation. The female offspring will be evaluated in relation to vaginal opening (puberty establishment), hormonal profile and regularity of the estrous cycle, using daily vaginal smears, which will be used to compare these females to those from rats of the control group (pump without nicotine).