[
Worm Breeder's Gazette,
1998]
There are data on the life span prolonging effect of pineal peptide preparation epithalamin in mice, rats and Drosophila melanogaster [1,2]. The purpose of this study was to investigate the effect of different concentrations of epithalamin in water solutions on nematode life span. In this experiment epithalamin was used in following dilutions 1:10*5, 1:10*6, 1:10*7, 1:10*8, 1:lO*9 and 1:10*10. Three adult animals (3 - 5 days old) were kept in microtitre wells containing 0.75 ml of liquid medium (with E. coli and without epithalamin) during 4 hours, then they were discarded and newborn larvae were transferred in next wells (with epitalamin in any concentration) every day (one worm in one well). This investigation was carried out in temperature +21C and in the darkness. The obtained results are presented in the following table. Table I Concentration of Longevity (days) epithalamin n mean +/- S.E. maximal Control 12 17.4 +/- 2.5 29 1:10*5 12 12.8 +/- 2.1 27 1:10*6 12 15.1 +/- 1.9 28 1:10*7 12 17.1 +/- 2.2 28 1:10*8 12 19.6 +/- 2.2 29 1:10*9 12 18.8 +/- 2.0 31 1:10*10 12 18.7 +/- 1.7 25
[
Worm Breeder's Gazette,
1997]
The purpose of this study was to investigate the effect of different concentrations of pineal indole hormone melatonin in water solutions on nematode life span. Melatonin was used in following dilutions: 1:10*3, 1:10*4, 1:10*5, 1:10*6, 1:10*7, 1:10*8, 1:10*9, and 1:10*10. Three adult animals (3-5 days old) were kept in microtitre wells containing 0.75 ml of liquid medium (with E. coli and without melatonin) during 4 hours, then they were transferred in next wells (with melatonin in any concentration) every day (one worm in one well). This investigation was carried out at temperature +21C and in darkness. The obtained results are presented in the table. Concentration of n Longevity (days) Melatonin Mean +/- S.E. Maximal Control 12 23.7 +/- 1.8 32 1:10*4 12 18.0 +/- 2.3 31 1:10*5 12 22.5 +/- 2.2 32 1:10*6 12 16.3 +/- 2.0# 27 1:10*7 12 15.6 +/- 2.4# 31 1:10*8 12 10.5 +/- 0.9# 14 1:10*9 12 11.3 -/- 1.6# 21 1:10*10 12 12.7 +/- 1.3# 22 #: The difference with control is significant, p Conclusion: If the water solution of melatonin was applied to C. elegans during the whole life span in above described conditions, it was not able to prolong the life span of these animals. In concentrations from 10*6 to 10*10 melatonin reduced the survival of nematoda. Acknowledgment: The authors wish to express their thanks to CGC for providing C. elegans (Bristol, N2) and E. coli OP50.