Development of insulin and epidermal growth factor receptors during the differentiation of rat preadipocytes in primary culture.

An homogeneous cell population isolated from the inguinal tissue of 3-day-old rats is able to proliferate in primary culture. In the presence of a physiological concentration of insulin (1.5 nM) it converts into cells exhibiting the morphology and the biochemical characteristics of adipocytes.

Characterization and repartition of epidermal growth factor-urogastrone receptors in gastric glands isolated from young and adult guinea pigs.

Physiological studies indicate that epidermal growth factor-urogastrone (EGF) acts on stomach epithelium as mitogen and modulator of acid secretion. Here, we studied the binding of 125I-EGF to gastric glands isolated from the guinea-pig fundus (acid-secreting part) and antrum. At 20 degrees C, the association of 125I-EGF to gastric glands was time-dependent (plateau at 90 min) and reversible (75-85% dissociation in 1 h).

[Effect of experimental diabetes and its treatment with insulin on the translation of RNAs and protein synthesis in rat enterocytes].

We examined the effect of diabetes on protein synthesis in intestinal epithelial cells. Isolated enterocytes of diabetic rats display a marked decrease (50%) in 3H-leucine incorporation into intestinal proteins as compared to normal cells. Treatment of diabetics with insulin restores the level of protein synthesis up to normal values.

Growth-promoting effect, biological activity, and binding of insulin in human intestinal cancer cells in culture.

The biological action and binding of insulin were tested in two human intestinal cancer cell lines originating from the duodenum (HUTU 80) and the colon (HT 29). After serum deprivation for 24 hr, insulin stimulated cell division and the incorporation of labeled precursors into RNA, protein, and DNA for both cell lines. The action on the RNA and protein was rapid and significantly different (1.

Evidence for the presence of insulin binding sites in isolated rat intestinal epithelial cells.

Insulin receptors have been demonstrated in isolated rat intestinal epithelial cells. The specific binding of 125I-insulin was time--and temperature--dependent, the optimal temperature of study being 15 degrees. Dissociation of bound 125I-insulin by an excess of unlabelled hormone was rapid and attained 66 +/- 2% in 2 h.