Spontaneous hemolytic activity of rat alveolar lining material

Abstract

During assays of the complement hemolytic activity in lavage fluids (LF) from humans and various laboratory animals (hamsters, rabbits, rats, guinea pigs), we have observed that rat bronchoalveolar lavages had a spontaneous, complement-independent, hemolytic activity to sheep red blood cells (SRBC). Rat lavage fluids were able to lyse sheep and autologous red blood cells at 2 degrees C as well as at 37 degrees C. Together with these observations, the inverse relationship that existed between the LF hemolytic activity and the calcium concentration in the incubation medium suggested that lysis could be due to the presence of large amounts of lysophospholipids in rat lavage fluid. However, thin layer chromatography did not reveal any abnormal amount in lysoderivative, whereas the free fatty acid (FFA) content was very high. Pure palmitic acid, at a concentration similar to that observed in LF from rat, was able to lyse SRBC (8.5 micrograms lysed 50% of 10(8) SRBC); lytic activity decreased when Ca++ or bovine serum albumin was added to the incubation mixture. FFA through their detergent effect, appear to account for the hemolytic activity of the rat alveolar lining material.

Increase in Lysolecithin Content of Brain Microsomes in Phenobarbitone‐Administered Rats and Its Relation to Lipid Peroxidation

“…The fact that formation of LPC has been implicated (Lindahl et al, 1986) as a factor involved in peroxidative membrane damage by xenobiotic stress, especially hemolysis, supports our contention. Because LPC is known to increase the pulmonary airway resistance and capillary permeability (Lindahl et al, 1986) and because the spontaneous hemolytic activity of rat alveolar lavage fluid is attributed partly to the content of LPC (Quesneau-Guilmont et al, 1988), the increased level of LPC in the present study may be considered to assume significance in the membrane function during phenobarbitone-induced neurotoxicity also. In control animals, the LPC content of whole brain, prior to microsome preparation, was found to be 12.…”