What is ECG of a patient showed tall T waves with normal rhythm. Laboratory examination showed serum potassium levels to be 7.5 mEq/L. Which of the following therapies will lead to fastest reduction in the serum potassium levels? and explain in detail?
Regulation of insulin secretion: The beta cells have a glucose sensing mechanism dependent on entry of glucose into Beta cells (through the aegis of a glucose transpoer GLUT2) and its phosphorylation by glucokinase. Glucose entry and activation of the glucoceptor indirectly inhibits the ATP-sensitive K+ channel resulting in paial depolarization of the beta cells This increases intracellular Ca2+ availability (due to increased influx, decreased efflux and release from intracellular stores) beta exocytotic release of insulin storing granules. Other nutrients that can evoke insulin release are--amino acids, fatty acids, and ketone bodies, but glucose is the principal regulator and it stimulates the synthesis of insulin as well. Glucose induces a brief pulse of insulin output within 2 min (first phase) followed by a delayed but more sustained second phase of insulin release. Glucose and other nutrients are more effective in invoking insulin release when given orally than i.v. They generate chemical signals 'incretins ' from the gut which act on cells in the pancreas to cause the anticipatory release of insulin. Glucagon and some of the peptides enhance insulin release by increasing cAMP formation in the beta cells. ESSENTIALS of MEDICAL PHARMACOLOGY SEVENTH EDITION:K.D TRIPATHI Page:259,260