[Liver and Its Lymph Region at Benzo[a]pyrene Effects in an Experiment].

Abstract

Background: Benzo[a]pyrene (BaP) is the widespread environmental toxicant with carcinogenic activity. BaP undergoes metabolic activation in the liver microsomal monooxygenase system, and its regional lymph nodes act as peripheral filters, purifying lymph formed in the liver. It remains an open question about the significance of the integral liver and lymphatic system work in supporting processes of adaptation and resistance to the BaP effects.

Objective: The purpose of our investigation was to study structural and metabolic changes in the liver and its lymph region in males Wistar rats weighing 180-220g.

Methods: Animals of the experimental group (n =20) daily for 3 days was performed BaP injections: intraperitoneal with 2 mg per 100g of body weight in 0.2-0.3 ml of olive oil. Rats in the control group (n =20) received in the same mode of injection of olive oil. The light and electron microscopy morphometric study of the liver and its regional lymph nodes morphometric analysis were performed. The intensity of lipid peroxidation in the liver was measured by the number of diene conjugates (DC), ketotriene conjugates (KC) and malondialdehyde (MDA).

Results: Simultaneous increase of the hepatic sinusoids relative area and the specific area of the regional lymph nodes sinus system under the BaP effect was found. At ultrastructural level dilatation of the Disse spaces, filling of cell detritus and collagen fibers bundles of these spaces were noted. Damage of nuclear apparatus, balloon transformation of granular endoplasmic reticulum profiles were found in hepatocytes, condensation of the mitochondrial matrix was observed. The relative squares of B-dependent zones increased and T-dependentparacortical zone reduced in the regional lymph nodes. The increase in the content of KC and MDA in liver was identified.

Conclusion: benzo[a]pyrene causes interrelated cascade of reactions in the liver and in its lymphatic region: a disturbance of the blood-lymph barrier morphological organization, and so obstruction of the lymphatic drainagefrom the organ. These promotes development of tissue hypoxia and apoptosis, protein synthesizing and energy cell apparatus disruptions, formation of lymphoid tissue temporary infiltrates in the liver.