Bernt Hökfelt

HISTOCHEMICAL DEMONSTRATION OF NORADRENALINE AND ADRENALINE IN THE ADRENAL MEDULLA

The optimal conditions for the histochemical demonstration of noradrenaline in the adrenal medulla by selective pigment formation at potassium iodate oxidation have been investigated. In addition the classical chromaffine reaction has been modified for the simultaneous demonstration of adrenaline and noradrenaline.

Increased Adrenaline Production Following Administration of 2-Deoxy-D-Glucose in the Rat.

Summary 2-deoxyglucose(2-DG) causes marked release of adrenaline from the adrenal medulla in the intact rat but not after adrenal denervation. The adrenaline released is to a great extent responsible for the hyperglycemia appearing after 2-DG, but other factors might also be involved. The inability of 2-DG to cause increased adrenaline secretion after denervation of the adrenal glands points to its action via a centrally located receptor mechanism regulating adrenaline secretion; this center seems not to be sensitive to the blood glucose level as such.

Plasma Free Fatty Acids after 2-Deoxy-D-Glucose in Intact, Adrenalectomized, Spinal and Hypophysectomized Rat.∗

Summary Plasma free fatty acids (FFA) were followed in the rat after injection of 2-deoxy-D-glucose (2-DG). In the intact animal 2-DG caused elevation of FFA, probably due to release of adrenal medullary hormones. In the hypophysectomized rat there was no change in FFA after 2-DG, in spite of pronounced secretion of catecholamines and independent of cortisone substitution. In the adrenalectomized rat 2-DG caused a marked decrease of FFA, likewise independent of cortisone medication. The authors are indebted to Dr. L. A. Carlson for valuable discussions.

Stimulation of pancreatic islet cells by 2-deoxy-D-glucose.

Summary In the intact rat 2-Deoxy-D-Glucose (2-DG) leads to decreased stainability and degranulation of the cytoplasm and increased nuclear size of both alpha and beta cells of the pancreatic islets. Maximal changes occurred 6 hours after administration of 2-DG. The findings are interpreted to indicate increased activity in both types of cells and the underlying regulatory mechanisms are discussed.