| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
ARTICLES |
Centro de Biología Molecular, Facultad de Ciencias, Universidad Autónoma (J.C.M., J.S., J.M.C.), and Instituto de Bioquímica, Centro Mixto UCM Facultad de Farmacia, Universidad Complutense (F.E., M.A., E.R., A.M.P.-L.), Madrid; and Area de Bioquímica, Facultad de Químicas, Universidad de Castilla-La Mancha (A.A.), Ciudad Real, Spain
Address all correspondence and requests for reprints to: Dr. José M. Carrascosa, Department of Molecular Biology, Molecular Biology Center, Faculty of Ciencias, Universidad Autónoma, 28049 Madrid, Spain.
Aging has been associated with peripheral insulin resistance in both humans and rats. However, the specific tissues that become insensitive to insulin before glucose homeostasis is altered remain to be elucidated. In the present work we studied the glucose metabolic index of a number of tissues known to be insulin sensitive in 3- and 24-month-old Wistar rats by measuring 2-deoxy-D-[1-3H]glucose uptake both under euglycemic-hyperinsulinemic conditions and in the basal state. Analysis of the glucose infusion rate to maintain normoglycemia during the clamp confirmed that the old rats show overall insulin resistance at both saturating and subsaturating insulin concentrations. The maximal response of glucose uptake to insulin as well as insulin sensitivity in red and white quadriceps were unaltered in old rats. In contrast, glucose uptake by soleus and diaphragm was poorly stimulated in old animals, and a marked decrease in insulin sensitivity was observed in both tissues. In heart, only the sensitivity to the hormone, not the maximal response, was impaired in old rats. In white adipose tissue, no significant stimulation was detected. We conclude that during aging in Wistar rats and before fasting plasma insulin and glucose levels become altered, specific tissues develop insulin resistance, whereas other remain insulin sensitive. We postulate that fat tissue plays a qualitative important role in eliciting the insulin resistance in old animals. Due to the metabolic characteristics of the aged Wistar rat, the changes reported might reflect what occurs in nonobese elderly humans, nongenetically committed to develop type 2 diabetes.
This article has been cited by other articles:
![]() |
R. T. Ribeiro, R. A. Afonso, M. P. Guarino, and M. P. Macedo Loss of Postprandial Insulin Sensitization During Aging J. Gerontol. A Biol. Sci. Med. Sci., June 1, 2008; 63(6): 560 - 565. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Garcia-San Frutos, T. Fernandez-Agullo, A. J. De Solis, A. Andres, C. Arribas, J. M. Carrascosa, and M. Ros Impaired Central Insulin Response in Aged Wistar Rats: Role of Adiposity Endocrinology, November 1, 2007; 148(11): 5238 - 5247. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Escriva, M L. Gavete, Y. Fermin, C. Perez, N. Gallardo, C. Alvarez, A. Andres, M. Ros, and J. M Carrascosa Effect of age and moderate food restriction on insulin sensitivity in Wistar rats: role of adiposity J. Endocrinol., July 1, 2007; 194(1): 131 - 141. [Abstract] [Full Text] [PDF] |
||||
![]() |
R Serrano, M Villar, C Martinez, J M Carrascosa, N Gallardo, and A Andres Differential gene expression of insulin receptor isoforms A and B and insulin receptor substrates 1, 2 and 3 in rat tissues: modulation by aging and differentiation in rat adipose tissue J. Mol. Endocrinol., February 1, 2005; 34(1): 153 - 161. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Perez, C. Fernandez-Galaz, T. Fernandez-Agullo, C. Arribas, A. Andres, M. Ros, and J. M. Carrascosa Leptin Impairs Insulin Signaling in Rat Adipocytes Diabetes, February 1, 2004; 53(2): 347 - 353. [Abstract] [Full Text] |
||||
![]() |
P. Tollet-Egnell, P. Parini, N. Stahlberg, I. Lonnstedt, N. H. Lee, M. Rudling, A. Flores-Morales, and G. Norstedt Growth hormone-mediated alteration of fuel metabolism in the aged rat as determined from transcript profiles Physiol Genomics, January 15, 2004; 16(2): 261 - 267. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. B. Arias, L. E. Gosselin, and G. D. Cartee Exercise Training Eliminates Age-Related Differences in Skeletal Muscle Insulin Receptor and IRS-1 Abundance in Rats J. Gerontol. A Biol. Sci. Med. Sci., October 1, 2001; 56(10): B449 - 455. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. L. Morin, E. C. Gayles, D. A. Podolin, Y. Wei, M. Xu, and M. J. Pagliassotti Adipose Tissue-Derived Tumor Necrosis Factor Activity Correlates with Fat Cell Size But Not Insulin Action in Aging Rats Endocrinology, December 1, 1998; 139(12): 4998 - 5005. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |