Lowering of Plasma Lipids, The Major Effect of Repeated Glucagon Administration in Rats

  • F. Gey
  • H. Georgi
  • E. Buhler
Conference paper

Abstract

The most prominent long lasting effect of repeated injection of commercial pancreatic glucagon (0.1–30 mg/kg s.c. twice daily) in fed and starving rats is a depression of the major plasma lipids. This lipid-lowering effect of glucagon becomes maximal after 2–3 days and persists for at least 4 weeks. After withdrawal of glucagon, the lipid levels, slowly return to normal. Plasma lipid depression occurs at glucagon doses (0.1 mg/kg) which have no comparable long-lasting effect on the level of other plasma components, such as glucose, FFA, α-amino nitrogen and urea, as well as on urinary excretion of urea. Dose-frequency curves suggest that lipid depression could also be obtained by the frequent release of small pulses of endogenous glucagon. On a molar basis, glucagon is more potent than other lipid-lowering hormones, like thyroxine and oestradiol. The injection of glucagon leads to a marked increase of the glucagon/insulin ratio in plasma, in spite of a considerable insulin release. Experiments in streptozotocin-treated rats with fully developed diabetes demonstrate that the lipid depression by glucagon does not depend on insulin. In consequence, a role of glucagon in the physiologic regulation of plasma lipids in the rat is suggested.

Keywords

Cholesterol Depression Urea Hydrocortisone Oestradiol 

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Copyright information

© Springer-Verlag New York Inc. 1977

Authors and Affiliations

  • F. Gey
    • 1
  • H. Georgi
    • 1
  • E. Buhler
    • 1
  1. 1.Research DepartmentsF. Hoffmann-La Roche and Co. Ltd.BaselSwitzerland

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