Insulin secretion in vitro

GLP is secreted from the lower gut in response to oral glucose, and GLP-1(7 36) amide also increases in the blood after feeding (Kreymann et al., 1988). GLP-1(7 36) amide has been found to be a potent stimulator of insulin secretion in vitro (Holst et al., 1987 Mojsov et al.. 1987), equivalent to or even greater than GIP (Shima etal.. 1988). Studies with the isolated perfused pancreas show a synergistic stimulatory effect of GLP-1(7 36> amide and GIP, suggesting, that several incretin factors may act simultaneously on the... 

Glucagon is believed to stimulate insulin secretion in man. Secretin, pancreozymin, and gastrin have all been found to stimulate insulin release. Acetylcholine and carbamylcholine stimulate insulin secretion in vitro in contrast, epinephrine and norepinephrine inhibit it. Thus, in pheochromocytoma, acute insulin responses are inhibited. 

Fig. 2u Insulin secretion in vitro". Insulin release from pieces of rabbit pancreas effected by glucose before and after addition of guinea pig antiinsulin serum. Note complete inhibition of I LA by anti bodies.

Fig. 3. Insulin secretion in vitro" Effect of d-Xylose on insulin secretion in vitro (pieces of rabbit pancreas).

Regarding stimulation of insulin secretion "in vitro" by amino acids, pieces of rat and rabbit pancreas mere incubated in media consisting of the usual buffer plus o.l, l.o and 10 mg amino acid/ml for 2 and 3 hours, respectively (Pfeiffer et al (1967), Yeboah (1967)). In Fig. 7 are shomn the responses of rabbit and rat pancreas "in vitro" to 1-leucine, the first amino acid shomn to induce insulin secretion "in vivo" in insulinoma patients (Cochrane, et al (1956)). Increases in Iffll concentrations up to 300% of the initial values recorded as 100 mere noted. Higher sensitivity of the rabbit than of the rat 0—... 

Fig. 6. Insulin secretion "in vitro" The effect of glucose (2.0 mg/ml) on the release of insulin from pieces of frog pancreas in relation to the seasons. Number of the frogs examined is given below the bars.

Fig. 8. Insulin secretion in vitro" Insulin secretion by pieces of rat pancreas stimulated by different doses of phenylalanine.

Fig, 9. Insulin secretion in vitro No insulin secretion from the rot pancreas induced by histidine and proline. 

Fig. 10. Insulin secretion In-vitro" Insulin release from pieces of rat...

Intestinal Hormones affecting Insulin Secretion In vitro... 

Fig. 13. Intestinal Hormones Affecting Insulin Secretion in Vitro...

Fig. 15. Insulin secretion in vitro" Insulin release from pieces of rat and rabbit pancreas, respectively, effected by Hb 419 and Tolbutamide in different concentrations. Note the approximately 100 and 1000 times more effective actions of Hb 419 on rat and rabbit pancreas, respectively.

Candela 3.L.R., R.R.Candela, 0.martin and T.Hernandez and Castilla Costazar Insulin secretion "in vitro" (prelim.comm.)... 

Intestinal Hormones effecting insulin secretion in vitro Secretin, Pancreocymin and Gastrin, Panel Discussion "Intestinal Function in Relation to Insulin Secretion". - 6th Congr. I.D.F. Stockholm, Aug.1967... 

Yeboah 3.E. Insulin secretion in vitro Stimulation der Insulinsekretion in vitro durch einzelne Aminosauren. 

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