Antioxidants in neoplastic cells: I. Changes in the antioxidative capacity of mouse neuroblastoma cells measured by a single-phase assay.

Cultured mouse neuroblastoma cells exhibit a striking increase in antioxidative capacity during the transition from logarithmically dividing cells to nondividing, neurite-bearing cells. Two physically separable phenomena are involved: (a) the membrane pellet of neurite-bearing cells is highly resistant to lipid peroxidation, and (b) the postmicrosomal supernatant of these cells inhibits peroxidation in rat liver mitochondria and other biological membranes. A precise, single-phase assay has been developed for assessing antioxidant levels in lipid extracts.

Substrate irradiation stimulation of the in vitro lactate-pyruvate interconversion reactions mediated by lactic dehydrogenase.

Experimental studies of the Comorosan effect are presented for the LDH-mediated interconversions of lactate and pyruvate. Consistent with the findings of the Comorosan group, the rate of the lactate/LDH reaction was found increased for crystalline lithium lactate irradiated with green light for times t comprising the manifold t = 15+30n sec, n = 0,1,2..

The Comorosan effect: single- and double-blind studies on the urea/urease system.

Characteristic alterations of enzymatic reaction rates by irradiation of the crystalline substrates for fixed periods with an Hg vapor lamp were reported by Comorosan in 1969. Results of single- and double-blind studies reported here support the validity of the key features of this striking and potentially important phenomenon.