Morphologic alterations in porcine endothelial cells by the plant toxin metabolite, monocrotaline pyrrole

Abstract

Animals treated with the pyrrolizidine alkaloid metabolite, monocrotaline pyrrole (MCTP), show a progressive pulmonary hypertension associated with interstitial edema and smooth muscle thickening of muscular vessels in the lung. To determine what effect the blood borne toxin has on the endothelium, primary tissue cultures were treated with MCTP and were examined using the scanning electron microscope.Porcine endothelial cells were isolated, cultured, then plated on tissue culture slides and Millipore filters. The effect of cell density was examined by plating at three different concentrations, the most dense (control cells) being confluent at time of fixation. Cells received no treatment, the vehicle (N,Ndimethylformamide), 5μg MCTP/ml or 50μg MCTP/ml 24 hours after plating and were allowed to grow for an additional four days.The most striking changes were cell hypertrophy and an alteration in the cell's plating character at a dose of 50μg MCTP/ml. Hypertrophy of the endothelial cells was evident at the 50μg MCTP/ml dose, at which the treated cells approached 4 to 5 times the size of the untreated cells.