Erkek Sıçanlarda Nonilfenolün Hipotalamus-Hipofiz-Adrenal Ekseni ve Epifiz Bezi Üzerine Etkilerinin İncelenmesi
Özet
Endocrine disrupting chemicals have been defined as substances that interfere with natural hormone mechanisms and disrupt the functioning of these mechanisms. Endocrine disruptors are chemicals that can show negative impact at very low concentrations. As a result of changes and developments in industry and technology, daily exposure to endocrine disrupting chemicals are increasing day by day.
Nonylphenol compounds are important due to their carcinogenic, teratogenic and mutagenic effects. Nonylphenol is a degradation product of alkylphenol ethoxylates, plastic compounds used in the manufacture of dentistry, food packaging, textiles, pesticides, detergents, colourant and cosmetics. Increasing demand and production for Nonylphenol Ethoxylates in recent years has led to their release into the environment. This directly resulted in increased exposure and accumulation in humans.
The Hypothalamus-Pituitary-Adrenal axis is a system responsible for maintaining homeostasis, especially related to stress. The specific hormones it secretes are of great importance in maintaining homeostasis, especially in controlling the physiological and chemical processes related to stress. Melatonin produced by the pineal gland regulates the circadian rhythm, sleep-wake cycle, thermal and immunological systems, and the menstrual cycle.
These systems control mechanisms that are extremely important for the body. The interaction of these systems and organs, which are extremely sensitive to endogens and especially to endocrine disruptors, can cause adverse effects on the entire endocrine system.
In this study, nonylphenol, one of the chemicals known to be endocrine disruptors, was administered as oral gavage to 21-day-old male Rattus norvegicus (Wistar albino) rats at doses of 5 mg/kg/day, 25 mg/kg/day and 125 mg/kg/day. At the end of the experiment, the histopathological effects on the liver, kidney, hypothalamus, pituitary, pineal and adrenal tissues were examined and the levels of melatonin, adrenocorticotropic hormone (ACTH), aldosterone, cortisol and glucose were examined in the serum samples. In addition, apoptosis was invastigated by TUNEL analysis in the pineal gland and pitiuitary gland.
According to the study results serum ACTH, and aldosterone levels significantly increased in the 5 and 25 mg/kg/day nonylphenol dose groups. Serum melatonin levels decreased in the 5, 25 and 125 mg/kg/day nonylphenol dose groups. Serum corticosterone amount increased significantly in the 125 mg/kg/day nonylphenol dose group. However, it was determined that this increase did not affect the serum glucose level. When the histopathological findings were evaluated, it was concluded that nonylphenol caused histopathological findings in the hypothalamus, pituitary, adrenal glands, liver and kidney tissues in all administration dose groups, but did not cause any pathological findings in the pineal gland. In addition, it was determined that nonylphenol caused apoptosis in liver and kidney tissues in all application groups.
