ISSN:
0263-6484
Keywords:
Insulin
;
peptide hormone receptor
;
prostatic epithelial cells
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Insulin receptors have been characterized in rat prostatic epithelial cells by using [125I]insulin and a variety of physicochemical conditions. The binding data at equilibrium (2h at 15°C) could be interpreted in terms of two populations of insulin receptors: a class of receptors with high affinity (Kd = 2·16 nM) and low binding capacity (28·0 fmol mg-1 protein), and another class of receptors with low affinity (Kd = 0·29 μM) and high binding capacity (1·43 pmol mg-1 protein). Proinsulin exhibited a 63-fold lower affinity than insulin for binding sites whereas unrelated peptides were ineffective. The specific binding of insulin increased by about 50 per cent after 96 h of fasting; this increase could be explained by an increase of both the number of the high affinity-low capacity sites and the affinity of the low affinity-high capacity sites. These results together with previous studies on insulin action at the prostatic level strongly suggest that insulin may exert a physiological role on the prostatic epithelium.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cbf.290040103
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