Influence of d-galactosamine hydrochloride on lipids and their fatty acid composition in plasma and liver of guinea pigs.

48 hrs after i.v. applications of 1 g/kg b.w. galactosamine hydrochloride to guinea pigs the total lipids of plasma, liver homogenate and isolated liver microsomes were extracted and separated by dialysis and thin-layer chromatography. The fatty acid fractions of total lipids (plasma), neutral lipids and total phospholipids (liver homogenate) as well as phosphatidylcholines and remaining phospholipids (liver microsomes) were analyzed by gaschromatography. In plasma the concentration of total lipids was unchanged in the galactosamine group. A slight decrease of the C16- and an increase of the C161- fatty acids were observed. In total liver homogenate neutral lipids increased 9-fold, and phospholipids 2.5 fold after galactosamine application. Specially there was a relative and absolute increase of the C16-, C16(1)-, C18(1)-, and C18(3)-fatty acids in the neutral lipids, whereas the C18- and C18(2)-Fatty acids were relatively diminished. Similar changes within the fatty acid fractions could be found to a minor degree in the phospholipids. 48 hours after application of galactosamine the phospholipid content in isolated liver microsomes increased about 2-fold. Likewise there was an absolute increase of nearly all fatty acid fractions as well in phosphatidylcholines as in the other phospholipids. In both phospholipid fractions the percentage of the C18-fatty acids decreased and a relative increase in C16-fatty acids was observed. Contrary to the findings in total liver, in the isolated microsomes predominantly saturated fatty acids (C16, C18) were found.