Glucose does not affect catecholamine stimulus-secretion coupling in rat adrenal medulla: relationship to low changes in osmolarity and to insulin.

摘要: Glucose levels were analyzed to see whether they directly affect the catecholamine release from chromaffin cells. We incubated isolated adrenal medullae of rats in Krebs-Hepes modified solutions with several glucose concentration, presence and absence carbachol or insulin. Transfer medulla a solution 11.1 mM 0.56 one caused an increase secretion. Relative change 25 50 enhanced effect mentioned above. An inhibitory was detected after transfer glucose. However, correction osmolarity mannitol NaCl switched back secretion basal all groups, sucrose indicated impairment release. No difference observed stimulated (100 microM carbachol) at levels. Further, insulin did not groups. Our results suggest that (1) variations do released; (2) rat highly sensitive hyperosmolarity extremely hyposmolarity; (3) Insulin had no acute direct on rats.