[Perifusion of monolayer-cultured B cells of the infant @entity35 : a comparative study of the effects of @entity6524 and XXXX ].

@entity368 @entity13638 @entity6524 @entity1922 @entity6525 @entity35 @entity864 @entity413 @entity1928
Cell culture techniques for monolayer islets of 3-week-old @entity35 pancreases and the responsiveness of B cells are described. In this procedure, whole pancreatic tissues from 3-week-old @entity35 were enzymatically dispersed and then cultured in a medium with 5.5 mM @entity413 plus 1 mM @entity6524 or with 5.5 mM @entity413 following a 3-day exposure to a medium with 5.5mM @entity413 plus 5 microM @entity13638 . The use of @entity6524 or @entity13638 allowed a selective deletion of fibroblasts, yielding large clusters that consisted mostly of islet cells. The immunocytochemical evaluation of the islet cells in these cultures showed that approximately 70% are B-cells, 20% A-cells, and 10% D-cells. On day 0, the response to 16.7 mM @entity413 included only a small rise in insulin secreted during the first and the second phase, and the response to 10 mM of @entity368 or @entity6525 was monophasic. After being cultured for 7 days, all three secretagogues markedly stimulated insulin secretion by B cells cultured in both media, resulting in an enhancement of the biphasic pattern. However, quantitative relationships differed. Thus, the total response from B cells in @entity6524 during a 30-min stimulation with @entity413 and @entity368 was significantly higher (1.6- and 1.9-fold respectively) than that from B cells in 5.5 mM @entity413 , although there was no significant difference in insulin secretion evoked by @entity6525 . Furthermore, in the former B cells, the amount of insulin secreted during the second phase was 84-94% of the total insulin secretion, and in the latter it was 66-76%. Addition of 1 mM @entity1922 and 10 microM @entity1928 resulted in a significant increase in insulin secretion by B cells in @entity6524 , whereas there was no difference in the increase of insulin secretion induced by 16.7 mM @entity413 and 200 nM @entity864 . In monolayer cultures that had been maintained in both media for 15 days, the second phase of insulin secretion due to the secretagogues was slightly decreased, but the biphasicity in the response was well preserved. In conclusion, the present results suggest that B cells of 3-week-old @entity35 may be still immature, and that the medium with @entity6524 is beneficial to the continued maturation of the B-cell function in vitro.
