Fine structural alterations induced by cortisol administration in non-adrenalectomized/non-fasted rat hepatocytes

Abstract Aim To investigate the impact of exogenously administered cortisol on non-adrenalectomized and non-fasted rat hepatocytes morphology, by means of electron microscopy. Emphasis has been given to alterations concerning particular organelles such as the nucleus, the endoplasmic reticulum, mitochondria and lysosomes. Material and method Accordingly to their treatment, 50 male Wistar rats were divided into two experimental groups: Group I ( N =30): Hydrocortisol 8 mg/100 g of body weight intraperitoneally. Group II ( N =20): Controls, given 2 ml of normal saline intraperitoneally. Animals were sacrificed 30 and 180 min after injection and liver specimens were taken for morphological study. Results In cortisol-treated cells: At 30 min, a significant decondensation of chromatin fibers was noticed, whereas the nuclear envelope and the nucleoli remained almost intact. Endoplasmic reticulum increased in size and complexity, as well as the number of mitochondria. The number of lysosomes slightly decreased. At 180 min, chromatin remained fully decondensated. Large nucleoli were apparent within the nucleus and the external membrane of the nuclear envelope was devoid of ribosomes. Conclusions Corticosteroids seem to promptly induce changes in hepatocytes ultrastructucture. The alterations mainly concern the size of nucleoli, the number of mitochondria and the complexity of endoplasmic reticulum, thus being consistent with an increased etabolic activity and protein synthesis.