EurekaMag.com logo
+ Site Statistics
References:
47,893,527
Abstracts:
28,296,643
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

The fetal heart insulin receptor responds differently to varying plasma insulin concentrations






Developmental Pharmacology and Therapeutics 10(3): 153-162

The fetal heart insulin receptor responds differently to varying plasma insulin concentrations

We investigated in vivo the effect of varying plasma concentrations of insulin on the 28- and 30-day-old fetal rabbit heart insulin receptors using plasma membranes. Alloxan induced maternal diabetes (n = 5) associated with fetal hyperglycemia and mild hyperinsulinemia (59.80 +/- 8.10 microU/ml versus a control of 26.25 +/- 3.70, p less than 0.01) increased the insulin receptor number from a control (30 d) of 168 +/- 1.01 to 320 +/- 34 X 10(10)/mg protein (p less than 0.01). Fetal administration of 1.0 U of insulin (n = 4) resulting in normoglycemia and moderately high plasma insulin concentrations (103.3 +/- 34.63 microU/ml versus a control of 13.72 +/- 1.60, p less than 0.05) did not alter the insulin receptor number (28 d). On the other hand fetal administration of 2.0 U of insulin (n = 4) resulting in hypoglycemia and severely high plasma insulin concentrations (288.3 +/- 51 microU/ml versus a control of 13.72 +/- 1.60, p less than 0.01) decreased the insulin receptor number from a control (28 d) of 200 +/- 23 to 82 +/- 23 X 10(10)/mg protein (p less than 0.01). The receptor affinity remained constant. We conclude that the downregulation (decrease) of the fetal heart insulin receptors in vivo is not a physiologic but a pharmacologic effect of insulin.


Accession: 006677035

PMID: 3301234



Related references

Devaskar S.U.; Karycki L.; Devaskar U.P., 1986: Varying brain insulin concentrations differentially regulate the fetal brain insulin receptor. We investigated the downregulating effect of varying states (physiologic and pharmacologic) of systemic and intracranial hyperinsulinism on the 28 to 30 day fetal rabbit brain insulin receptor. Alloxan-induced maternal diabetes (n=5) produced mild...

Montagut, G.; Onnockx, S.; Vaqué, M.; Bladé, C.; Blay, M.; Fernández-Larrea, J.; Pujadas, G.; Salvadó, M.Josepa.; Arola, Lís.; Pirson, I.; Ardévol, A.; Pinent, M., 2010: Oligomers of grape-seed procyanidin extract activate the insulin receptor and key targets of the insulin signaling pathway differently from insulin. Procyanidins are bioactive flavonoid compounds from fruits and vegetables that possess insulinomimetic properties, decreasing hyperglycaemia in streptozotocin-diabetic rats and stimulating glucose uptake in insulin-sensitive cell lines. Here we sh...

Mcmenamy K.; Holtzclaw L.; Sadiq F.; Devaskar S., 1988: The effect of hyperglycemia with high low insulin concentrations on fetal and maternal brain and liver insulin receptor glycosylation. Clinical Research 36(6): 899A

Sesti, G.; Marini, M.A.; Montemurro, A.; Borboni, P.; D.C.la, G.; Bertoli, A.; D.P.rro, R.; Lauro, R., 1991: Evidence that human and porcine insulin differently affect the human insulin receptor: studies with monoclonal anti-insulin receptor antibodies. Binding studies have been carried out with radioiodinated monoclonal antibodies directed to various epitopes of the insulin receptor in order to detect differences between human and porcine insulin in the interaction with the human insulin recepto...

Gallaher, B.W.; Oliver, M.H.; Eichhorn, K.; Kessler, U.; Kiess, W.; Harding, J.E.; Gluckman, P.D.; Breier, B.H., 1994: Circulating insulin-like growth factor II/mannose-6-phosphate receptor and insulin-like growth factor binding proteins in fetal sheep plasma are regulated by glucose and insulin. We have reported previously that levels of insulin-like growth factor I (IGF-I) and IGF-II in fetal sheep plasma decrease with maternal starvation and increase following an infusion of glucose to the starved fetus, while a fetal infusion of insuli...

Oliver, M.H.; Harding, J.E.; Breier, B.H.; Gluckman, P.D., 1996: Fetal insulin-like growth factor (IGF)-I and IGF-II are regulated differently by glucose or insulin in the sheep fetus. We investigated the effect of restoration of normoglycaemia or normoinsulinaemia in fetuses of starved ewes on plasma IGF-I and IGF-II concentrations. Paired maternal and fetal blood samples were taken during an initial 2-day control period, after...

Gewolb I.H.; O'brien J.; Palese T.A.; Phillip M., 1992: High glucose and insulin decrease insulin receptor mrna and insulin receptor tyrosine kinase activity in fetal rat lung explants. Pediatric Research 31(4 PART 2): 308A

Varewijck, A.J.; Yki-Järvinen, H.; Schmidt, R.; Tennagels, N.; Janssen, J.A.M.J.L., 2013: Concentrations of insulin glargine and its metabolites during long-term insulin therapy in type 2 diabetic patients and comparison of effects of insulin glargine, its metabolites, IGF-I, and human insulin on insulin and igf-I receptor signaling. We investigated: <I>1</I>) the ability of purified glargine (GLA), metabolites 1 (M1) and 2 (M2), IGF-I, and NPH insulin to activate the insulin receptor (IR)-A and IR-B and IGF-I receptor (IGF-IR) in vitro; <I>2</I>) plasm...

Szewczyk K.; Devaskar S.; Devaskar U., 1985: Varying concentrations of fetal hyperinsulinemia differentially affect the myocardial insulin receptors. Clinical Research 33(4): 903A

Mohamed-Ali, V.; Pinkney, J.H.; Panahloo, A.; Goodrick, S.; Coppack, S.W.; Yudkin, J.S., 1997: Relationships between plasma leptin and insulin concentrations, but not insulin resistance, in non-insulin-dependent (type 2) diabetes mellitus. In non-diabetic subjects, insulin concentrations and insulin resistance are clearly connected, and both correlate with leptin levels, making interpretations about mechanisms difficult. In non-insulin-dependent (Type 2) diabetes mellitus (NIDDM), h...