PLATELET-ACTIVATING FACTOR IN THE CNS

Platelet-activating factor (PAF) is a phospholipid synthesized in a variety of cells throughout the body. Platelet-activating factor has been identified in the CNS and has a number of diverse physiological and pathological functions. It has been shown to be a modulator of many CNS processes, ranging from long-term potentiation (LTP) to neuronal differentiation. Excessive levels of PAF appear to play an important role in neuronal cell injury, such as that resulting from ischaemia, inflammation, human immunodeficiency syndrome (HIV) and meningitis. The beneficial effects of PAF receptor antagonists are many and give rise to possible therapeutic strategies for neurotrauma. Copyright © 1996 Elsevier Science Ltd.     

THE EFFECTS OF A MET-ENKEPHALIN ANALOGUE ON ACTH, β-LPH, β-ENDORPHIN AND MET-ENKEPHALIN IN PATIENTS WITH ADRENOCORTICAL DISEASE

Thirteen patients with either Addison's disease, or Cushing's disease treated by bilateral adrenalectomy, were infused with the long-acting met-enkephalin analogue DAMME. In patients with Addison's disease significant and pronounced falls in ACTH and N- and C-terminal beta-LPH were seen; chromatography suggested that beta-endorphin fell concomitantly. Three out of four patients with Cushing's disease who had not received pituitary irradiation, also showed a decrease in plasma ACTH and N- and C-terminal beta-LPH; however, no change was seen in any of the irradiated patients. The changes were naloxone reversible. The levels of plasma met-enkephalin were normal and did not change after DAMME in any group of patients. These results are interpreted as suggesting that there are inhibitory opiate receptors controlling the release of ACTH, beta-LPH, and beta-endorphin.