Estudi dels efectes de l'exposició a l'unari en la reproducció i la conducta. Influencia de l'estres
Depleted uranium has been used in medial and industrial applications for decades but only since its use in military conflicts in the Gulf and the Balkans has public concern been raised about potential health consequences from exposure to it.
Moreover, uranium contamination becomes dispersed across the natural environment, thus entering the food chain. It means that for certain populations, the chemical toxic effects of uranium intake can be a matter of notable concern.
On the other hand, stress is a highly individualized response of an organism to external or internal challenges. It is obvious that general population, as well as the military personnel are probably subjected to remarkable stressful events or experiences.
It is also well known that neurobehavioral changes, together with physiological and biochemical alterations, are common response to stress. Taking into account that humans be potentially exposed to uranium, while they can be also concurrently subjected to stressful situations, the consequences could become apparent as an interaction,
like an increase or a decrease of the effects.
The main objective of the present study was to assess whether stress could enhance the potential adverse effects of uranium (UAD) on reproduction and behaviour.
Neither UAD doses tested nor restraint stress induces alterations in the behavioural tests carried out in adult male rats exposed to uranium.
The results of the current study suggest that chronic UAD exposure in males affects sperm production and morphology, as well as reveal dose related tubular and interstitial alterations of the testes. Moreover, histopathological examination of the kidneys revealed an angiomatose transformation in UAD-exposed animals.
In brain, testes and kidneys, graded doses of UAD elicit depletion of the antioxidant defence system of the rat and induce oxidative stress.
General data on pregnancy outcome measures show, neither in the number of total implants per litter nor in the number of viable and nonviable implants per litter significant differences among groups. However, UAD produced a significant (not dose-related) decrease in the pregnancy rate of treated rats.
In the current study, restraint stress did not enhance the induced physical, neuromotor and behavioural changes in the offspring of UADexposed male rats.
This doctoral thesis shows that oral UAD exposure in rats causes signs of toxicity in testes, kidneys and brain. The results of this investigation show that at the current UAD doses, restraint stress did not enhance the uranium-induced adverse effects in male rats. However, the influence of stress on these potential toxic effects cannot be discarded.
Advisor:Sanchez Cervelló, Domingo J.; Gómez Arnaiz, Mercedes
School:Universitat Rovira i Virgili
Source Type:Master's Thesis
Keywords:departament de ciències mèdiques bàsiques
Date of Publication:02/21/2006