Hypoglycaemic effect of liposome-entrapped insulin administered intragastrically into rats.
The possibility of using liposomes as intragastric carriers of insulin was investigated in normal and diabetic rats. 1-3 units of insulin entrapped in dipalmitoylphosphatidylcholine cholesterol liposomes administered to normal rats decreased blood-glucose levels in 4 h to about 77% of those before treatment. Higher doses (4-2 and 8-4 units) extended this effect over 24 h. 1-0 units of insulin entrapped in the same liposomes had an even more pronounced effect in diabetic rats--levels of blood-glucose were reduced to 57% of pretreatment values after 4 h. Insulin entrapped in egg phosphatidylcholine/cholesterol liposomes was less effective. The effectiveness of liposome-entrapped insulin was similar in diabetic rats whether administered intragastrically or intraperitoneally but free insulin was more effective intraperitoneally. Radioimmunoassay of insulin in the serum confirmed that lowering of blood-glucose after the intragastric administration of liposome-entrapped insulin was related to the entry of at least some of the insulin into the circulation.
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002784:Cholesterol; D003920:Diabetes Mellitus / Q000097:blood / Q000188:drug therapy*; D005260:Female; D007274:Injections, Intraperitoneal; D007328:Insulin / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use; D008081:Liposomes; D008297:Male; D010063:Ovum; D014677:Pharmaceutical Vehicles; D051381:Rats; D013270:Stomach; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin; D008081:Liposomes; D014677:Pharmaceutical Vehicles; D002784:Cholesterol