Insulin and insulin-like growth factor I differentially induce alpha1-adrenergic receptor subtype expression in rat vascular smooth muscle cells. 1996

Z W Hu, and X Y Shi, and B B Hoffman
Department of Medicine, Stanford University School of Medicine, California 94304, USA.

Hyperinsulinemia has been implicated as an important risk factor for the development of accelerated cardiovascular disease. We wondered if insulin or IGF-I induced expression of alpha1 adrenergic receptors in vascular smooth muscle cells (VSMCs) which could enhance smooth muscle contraction and cell growth activated by catecholamines. Rat aortic VSMCs were incubated with insulin or IGF-I for various times and expression of alpha1 receptors was detected using [3H]prazosin binding. Both insulin and IGF-I increased alpha1 receptor number; also, these peptides increased expression of the alpha1D receptor gene with no change in expression of the alpha1B receptor gene as detected by RNase protection assays. Using Western blotting, we found that these peptides increased expression of the alpha1D receptor subtype in these cells. Increased expression of the alpha1D receptor mRNA was inhibited by the receptor tyrosine kinase inhibitor genistein and the PI 3-kinase inhibitor wortmannin but was not inhibited by protein kinase C inhibitor H7 or the L-type calcium channel blocker nifedipine. Preincubation of cells with insulin or IGF-I enhanced subsequent norepinephrine stimulation of mitogen activated kinase activity. These results suggest that insulin/IGF-I regulate expression of alpha1 receptors in VSMCs and potentially enhance the effects of catecholamines in settings of hyperinsulinemia.

UI MeSH Term Description Entries
D007328 Insulin A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1). Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
D007334 Insulin-Like Growth Factor I A well-characterized basic peptide believed to be secreted by the liver and to circulate in the blood. It has growth-regulating, insulin-like, and mitogenic activities. This growth factor has a major, but not absolute, dependence on GROWTH HORMONE. It is believed to be mainly active in adults in contrast to INSULIN-LIKE GROWTH FACTOR II, which is a major fetal growth factor. IGF-I,Somatomedin C,IGF-1,IGF-I-SmC,Insulin Like Growth Factor I,Insulin-Like Somatomedin Peptide I,Insulin Like Somatomedin Peptide I
D008297 Male Males
D009131 Muscle, Smooth, Vascular The nonstriated involuntary muscle tissue of blood vessels. Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D011224 Prazosin A selective adrenergic alpha-1 antagonist used in the treatment of HEART FAILURE; HYPERTENSION; PHEOCHROMOCYTOMA; RAYNAUD DISEASE; PROSTATIC HYPERTROPHY; and URINARY RETENTION. Furazosin,Minipress,Pratsiol,Prazosin HCL,Prazosin Hydrochloride,HCL, Prazosin,Hydrochloride, Prazosin
D011493 Protein Kinase C An serine-threonine protein kinase that requires the presence of physiological concentrations of CALCIUM and membrane PHOSPHOLIPIDS. The additional presence of DIACYLGLYCEROLS markedly increases its sensitivity to both calcium and phospholipids. The sensitivity of the enzyme can also be increased by PHORBOL ESTERS and it is believed that protein kinase C is the receptor protein of tumor-promoting phorbol esters. Calcium Phospholipid-Dependent Protein Kinase,Calcium-Activated Phospholipid-Dependent Kinase,PKC Serine-Threonine Kinase,Phospholipid-Sensitive Calcium-Dependent Protein Kinase,Protein Kinase M,Calcium Activated Phospholipid Dependent Kinase,Calcium Phospholipid Dependent Protein Kinase,PKC Serine Threonine Kinase,Phospholipid Sensitive Calcium Dependent Protein Kinase,Phospholipid-Dependent Kinase, Calcium-Activated,Serine-Threonine Kinase, PKC
D002478 Cells, Cultured Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others. Cultured Cells,Cell, Cultured,Cultured Cell
D004305 Dose-Response Relationship, Drug The relationship between the dose of an administered drug and the response of the organism to the drug. Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005786 Gene Expression Regulation Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation. Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia

Related Publications

Z W Hu, and X Y Shi, and B B Hoffman
August 1996, European journal of biochemistry,
Z W Hu, and X Y Shi, and B B Hoffman
August 1993, The Journal of biological chemistry,
Z W Hu, and X Y Shi, and B B Hoffman
December 1991, Hypertension (Dallas, Tex. : 1979),
Z W Hu, and X Y Shi, and B B Hoffman
January 1997, Cardiovascular research,
Z W Hu, and X Y Shi, and B B Hoffman
September 2000, Journal of the renin-angiotensin-aldosterone system : JRAAS,
Copied contents to your clipboard!