Neurobehavioural effects of exposure to fluoride in the earliest stages of rat development

FERNANDA GUMILAR; MARIANA BARTOS; CRISTINA BRAS; CRISTINA GALLEGOS; ALEJANDRA MINETTI; LEDA GIANNUZZI

Florencia

Congreso; 53rd Annual Meeting of the International Association of Forensic Toxicologists (TIAFT); 2015

TIAFT

IntroductionIt is known that exposure to high concentrations of Fluoride (F) produces deleterious health effects in human population. However, in the last years it has been concluded that low concentrations of F may have adverse health effects as well. Transplacental passage of F and its incorporation into fetal tissues has been demonstrated. Therefore, the purpose of the present work was to study the effects of the exposure to low levels of F during pregnancy and lactation on the central nervous system functionality.AimsThe purpose of the present study was to study in young and adult rats, the effect of exposure to low concentrations of F during pregnancy and lactation, on sensory-motor reflexes and on the anxiety level.MethodsPregnant female rats were exposed to 5 and 10 mg/L F in drinking water during pregnancy and lactation. Starting on postnatal day 3, each pup received a battery of developmental tests: Righting reflex, Cliff aversion and Negative geotaxis. Also, the ear and eye opening were assessed. One test trial per day was given to the pups on each test. The dependent variable analysed for each test consisted in the postnatal day until the following criteria were reached by each pup. In the 45- and 90-day-old offspring, anxiety was determined using an elevated plus maze. The plus maze consisted of two arms enclosed and located perpendicularly to two open arms. The test exploits a rodent?s natural conflict between avoidance and exploration of open and elevated areas. The rats were placed in the center of the maze and were allowed to explore the maze freely for 5 min. The following parameters were calculated: i) percentage of time spent in the open arms, ii) percentage of entries in the open arms, and iii) total number of arm entries. Increased time spent and entries in the open arms are consistent with a decrease in anxiety behavior. ResultsA significant delay in the development of eye opening was observed in all offspring whose mothers had been exposed to the two F concentrations tested (p0.01for 5mg/LF and p