Effect of lysolecithin and lecithin of blood serum on the sensitivity of heart to acetylcholine

Phospholipids in mitochondrial dysfunction during hemorrhagic shock

Energy deficiency plays a key role in the development of irreversible shock conditions. Therefore, identifying mitochondrial functional disturbances during hemorrhagic shock should be considered a prospective direction for studying its pathogenesis. Phospholipid (PL)-dependent mechanisms of mitochondrial dysfunction in the brain (i.e., in the frontal lobes of the cerebral hemispheres and medulla oblongata) and liver, which, when damaged, leads to an encephalopathy, are examined in this review. These mechanisms show strong regional specificity. Analyzing the data presented in this review suggests that the basis for mitochondrial functional disturbances is cholinergic hyperactivation, accompanied by a choline deficiency and membrane phosphatidylcholine (PC) depletion. Stabilization of the PL composition in mitochondrial membranes using "empty" PC liposomes could be one of the most important methods for eliminating energy deficiency during massive blood loss.

Effect of lysolecithin on blood vessel reactivity and of some ethers and esters of glycerophosphocholine and phosphocholine, respectively, on aggregation of rat platelets

Infusion of lysolecithin (LPC; e.g. 88 microgram/ml for 0.5-1.0 min) did not significantly impair the vasopressor action of norepinephrine (NE), prostaglandin F2 alpha (PGF2 alpha) and extract of posterior pituitary (EPP) in the isolated perfused hind legs of rats. In other words, vascular smooth muscle behaves differently from the smooth muscle of the guinea-pig small intestine, since, in the latter, contractions evoked by acetylcholine, prostaglandins etc., are inhibited by LPC. Triton X 100 which, by comparison, was used as a detergent effective on the guinea-pig small intestine, depressed the vasopressor effect of NE, PGF2 alpha and EPP. LPC, at low concentrations (40 mumol/l), potentiated (15% max.) ADP-induced platelet aggregation (PA) in rat PRP but, at high concentrations, inhibited PA (IC50 = 390 mumol/l). 2-Hexadecylglycerophosphocholine and its short-chain 1-alkyl ethers, which are structurally related to platelet-activating factor, as well as some long-chain alkanol phosphocholine esters, were somewhat more active than LPC. Dipalmitoyllecithin (4-700 mumol/l) was without any effect.