CYSTIC FIBROSIS (CF) AND RESPIRATORY ENERGY PRODUCTION

Serum, saliva and fibroblast culture media from homozygotes (HM) and heterozygotes (HZ) with CF induce inhibition of ciliary activity or ion transport in a number of biological systems. The possibility that this inhibition may result from respiratory energy alterations was investigated in the nauplii of brine shrimp Artemia Salina (N-BS). “Spent” culture media from HM and HZ fibroblast cultures reduced respiratory energy production by isolated mitochondria from N-BS. This was determined by the micromoles phosphorus esterified/microatoms oxygen consumed (P/O). P/O ratios were: normal controls (NC) 1.6±.3 (10)*; HZ, 1.3±.3 (6); and HM, 1.2±.3 (8). The probability is high that NC and HM are different (P=0.01) but not NC and HZ (P<0.05). When intact N-BS were exposed to mixed saliva from NC, HM and HZ, the O2 consumptions (ul O2/hour nauplius) were: HM, 0.017±0.012 (10), HZ, 0.049±0.010 (10) and NC, 0.087±0.003 (10). HM and HZ values were statistically different from NC and from each other with P<.001. The results suggest that fibroblast culture media and mixed saliva from HM and HZ decrease respiration and mitochondria) energy production of N-BS and may provide a common effect that quantitatively detects previously described CF factors. This effect on oxidative energy production may provide further insight into the pathogenesis of CF. Furthermore, it appears that N-BS could be used to develop a bioassay for detection of HZ for CF. *Numbers in parentheses indicate number of experiments.