The contents of the heterogenous group of polyisoprenoids was found about two orders of magnitude lower in seeds than the amount of polyprenols and/or their carboxylic esters accumulated during vegetation season in leaves. In contrast to leaves, no seeds were found containing more than 0.5 mg of these lipids per gram of dry tissue. Almost 50% had less than 0.01 mg/g — the amount which is the limit of detection by the procedure used in this work. In gymnosperms (10 representatives of Cupressaceae, Pinaceae and Taxaceae) the polyprenol spectra in seeds and in needles were similar. In angiosperms (25 representatives of 13 botanical families) the polyisoprenoid mixture in seeds resembled the minor, additional subfamily found in leaves.
The uptake of C95[l-3H]dolichol in the form of liposomes into rat brain after the intracerebral and intraperitoneal injection was investigated. Efficient, time-dependent uptake of dolichol into the brain was observed exclusively after the intraventricular injection. Within 24 h after the injection about 10% of the applied dolichol was found in the brain and 1.5% in liver. The distribution of dolichol in various parts of rat brain decreased in the order: cerebellum > midbrain > grey matter and brain stem > white matter. Sevtn days after the injection total radioactivity in the brain decreased and concomitantly a significant increase was observed in blood circulating and liver of the rat. The highest activity was found in grey matter and it remained a few times higher in comparison with that in whitematter. About 80% of the dolichol taken up by the brain membrane was recovered in the following subcellular fractions: crude nuclear fraction > microsomes > mitochondria > synaptosomes > myelin.