ISSN:
1573-8221
Keywords:
liposomes
;
intravenous injection
;
phosphatidylcholine
;
diester analog of phosphatidylcholine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract Changes in the content of liposomes prepared from egg phosphatidylcholine and its nonhydrolyzed diester analog 1,2-dipalmitylphosphatidylcholine in the blood and liver in the course of time after intravenous injection of the liposomes into mice were studied. Cholesteryl-[1-14C]-oleate was used as marked. The kinetics of blood clearance of the two types of liposomes consists of two phases: an initial rapid phase connected with removal of intact liposomes from the blood, and a subsequent slow phase. Replacement of phosphatidylcholine by its diester analog did not cause any delay in the disappearance of liposomes from the blood during the first phase, but reduced the rate of decrease of radioactivity of the blood somewhat during the slow phase. The results show that lipolytic enzymes capable of hydrolyzing the ester bonds in the 1 and 2 positions of phosphatidylcholine evidently do not participate in the mechanisms of removal of intact liposomes from the blood stream. Since liposomes prepared from the diester analog of phosphatidylcholine are rapidly cleared from the blood stream and since they cause unfavorable side effects, they appear to have no prospects for use as drug carriers capable of circulating in the blood stream for a long time.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00869212
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