ABSTRACT
Objective To study the relationship between cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway and glutamine-stimulated insulin secretion.Methods In the prerequisite of the existence of glucose(0.25 mmol/L),the insulin secretion of βHC9 cells was stimulated with different concentrations of glutamine (0.0,0.5,1.0,2.0,5.0 mmol/L),then culture liquids were extracted and centrifugalized,and the insulin levels in the cell culture liquids and the cAMP levels in βHC9 cells were determined,so as to study the effects of glutamine stimulation on the insulin level in cell culture liquids and cAMP levels in βHC9 cells were assayed.Results In the prerequisite of the glucose existence,with the increasing of the concentrations of glutamine(0.0,0.5,1.0,2.0,5.0 mmol/L),the insulin levels[0.0 ng/(mL · million),19.1 ng/(mL · million),29.1 ng/(mL · million),30.1 ng/(mL · million),33.9 ng/(mL · million)] in cell culture liquids and the cAMP levels (0.0 pmol/million,40.0 pmol/million,51.5 pmol/million,52.5 pmol/million,61.3 pmoL/million) in βHC9 cells increased accordingly.Conclusion Glutamine has amplifying effect on glucose stimulated insulin secretion,such amplifying effect needs the existence of cAMP to be prerequisite.
ABSTRACT
Objective To investigate the clinical features of these children with congenital hyperinsulinism (CHI) who had no response to diazoxide and provide a theoretical foundation for the formulation of CHI treatment strategy.Methods Eighteen patients with CHI who had no response to diazoxide hospitalized in Beijing Children's Hospital from 2008 to 2012 were chosen as research subjects.Their clinical data were analyzed retrospectively.Results There were 18 patients with persistent hypoglycemia after using diazoxide,which indicated that they had no response to diazoxide.Twelve patients of them were born as macrosomia and their onset age was less than 6 months.Half of the children(9/18 cases) even had hypoglycemia in neonatal period.All the manifestations were conformed to the clinical characteristics of ATP-sensitive potassium channel CHI.Four children who were unresponsive to diazoxide received octreotide treatment,and it was effective on them.Four patients had a near-total pancreatectomy.After a long-term followup study,their blood sugar maintained a normal level,and they did not appear serious postoperative complications.Conclusions Children with CHI who have no response to diazoxide are characterized by coming earlier and higher birth weight.Octreotide is proposed in case of non-response to diazoxide.When medical treatment is not efficient in prevention of hypoglycemia,a subtotal pancreatectomy has to be considered as a last resort.