Testosterone regulates metabolism of plasma chylomicrons in rats

Journal Article · Sun Jul 01 00:00:00 EDT 1990 · Arteriosclerosis (Dallas); (USA)

DOI:https://doi.org/10.1161/01.ATV.10.4.591· OSTI ID:6643275

Staprans, I; Rapp, J H; Pan, X M; Ong, D L; Feingold, K R ^[1]

---

1. Lipid Research Laboratory, San Francisco, CA (USA)

Previously we demonstrated a marked sex difference in the metabolism of chylomicrons in adult rats. In males, radiolabeled chylomicrons displayed a longer dwell time on endothelial surfaces, which resulted in a decreased chylomicron uptake by the liver. The increased rate of chylomicron metabolism in females was associated with increased postheparin lipoprotein lipase activity. In the present study, we have investigated the effects of physiological doses of sex steroid hormones on the metabolism of chylomicrons and postheparin lipoprotein lipase activity. No sex differences were found in prepubertal animals. We also found no difference in chylomicron metabolism in control female, castrated female, estrogen-treated female, castrated male, and estrogen-treated male rats. However, control male, testosterone-treated male, and testosterone-treated female rats showed increased endothelial binding of chylomicrons and decreased chylomicron uptake by the liver. Postheparin lipoprotein lipase activity also was decreased by testosterone administration. In parallel with the alterations in chylomicron metabolism, serum high density lipoprotein levels in male rats decreased with testosterone administration. These results indicate that the differences in chylomicron metabolism, postheparin lipoprotein lipase activities, and serum high density lipoprotein levels observed between male and female rats are due to testosterone.

• OSTI ID: 6643275
• Journal Information: Arteriosclerosis (Dallas); (USA), Vol. 10:4; ISSN 0276-5047
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CHYLOMICRONS
METABOLISM
LIPASES
ENZYME ACTIVITY
TESTOSTERONE
BIOCHEMICAL REACTION KINETICS
CHOLESTEROL
ENDOTHELIUM
HEPARIN
ISOTOPES
LIPOPROTEINS
LIVER
MYOCARDIUM
RATS
SEX DEPENDENCE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
AMINES
ANDROGENS
ANDROSTANES
ANIMAL TISSUES
ANIMALS
ANTICOAGULANTS
BODY
CARBOHYDRATES
CARBOXYLESTERASES
CARDIOVASCULAR SYSTEM
DIGESTIVE SYSTEM
DRUGS
ENZYMES
ESTERASES
GLANDS
HEART
HEMATOLOGIC AGENTS
HORMONES
HYDROGEN COMPOUNDS
HYDROLASES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KETONES
KINETICS
LIPIDS
MAMMALS
MUCOPOLYSACCHARIDES
MUSCLES
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANS
POLYSACCHARIDES
PROTEINS
REACTION KINETICS
RODENTS
SACCHARIDES
STEROID HORMONES
STEROIDS
STEROLS
TISSUES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques
550501 - Metabolism- Tracer Techniques