Effect of long-term nickel ingestion on insulin binding and antilipolytic response in rat adipocytes.
Male Wistar rats of the third generation of rats drinking 200 micrograms Ni2+/mL as NiCl2 in their drinking water were studied. Basal plasma glucose and insulin levels were unchanged. Epididymal adipocytes from Ni2(+)-fed rats showed an increased insulin binding with a slight increase in apparent insulin affinity (ED50: Ni2(+)-fed rats 2.8 x 10(-9) M and controls 5 x 10(-9) M) with no change in insulin receptor numbers (Ni2(+)-fed rats 143,000 +/- 12,000 (6) receptors/cell and controls 126,000 +/- 13,000 (5]. Moreover, a decreased sensitivity to the antilipolytic response of insulin was also observed in adipocytes from Ni2(+)-fed rats. These events could represent actions of Ni2+ both at the receptor and post-receptor insulin levels. Several possible mechanisms involved in the process are suggested.
Mayor
P
P
Department of Biochemistry, Faculty of Medicine, Madrid, Spain.
Cabrera
R
R
Ribas
B
B
Calle
C
C
D000273:Adipose Tissue / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D005990:Glycerol / Q000378:metabolism; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D007457:Iodine Radioisotopes; D008066:Lipolysis / Q000187:drug effects*; D008297:Male; D009532:Nickel / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011972:Receptor, Insulin / Q000187:drug effects / Q000378:metabolism
D007328:Insulin; D007457:Iodine Radioisotopes; D009532:Nickel; D011972:Receptor, Insulin; D005990:Glycerol