[Structural and functional characteristics of the lower tracheobronchial lymph nodes in the rat after administration of dimethyl sulfate].

By means of microanatomical methods the inferior tracheobronchial lymph nodes in 36 Wistar rats have been investigated, when the animals have been subjected to the effect of dimethylsulfate (DMS) vapors. The effect of the substance in doses 0.1 and 2.0 mg/m3 for 2 and 14 days has been studied. Comparison of relative parameters of the structural components areas and the cytological profile of the lymph nodes has been performed. DMS effects for 2 and 14 days in the maximal tolerance concentration (MTC) results in increasing area of the connective tissue stroma and the cortical substance, in comparison with the control, as well as in decreasing area of the medulla substance. At the contact with DMS for 2 days (at a corresponding MTC) certain changes of the nodular cytological profile are noted. They demonstrate that to the given time of the experiment the adaptive processes in the lymph nodes have no time to develop completely. DMS effect for 14 days in the same concentration produces an increased destruction of cellular elements and inhibits the plasmocellular reaction intensity (in comparison to the control and the experiment for 2 days). DMS maximal concentration (2.0 mg/m3) results in decreasing area of the lymphoid noduli with germinative centers. Intensity of mitotic processes decreases and autoimmune processes develop.