In the higher ranked animals the alteration of the environment can provoke a uniform reaction named general adaptation system (GAS), which is a manifestation of stress, caused by different stressors. During GAS certain organs show typical reactions and two members of the hormonal system are activated: epinephine and glucocorticoids. As the unicellular ciliate Tetrahymena also synthesize most of the mammalian-like hormones (except steroids), it can respond to stress by a hormonal reaction. The main differences, related to the mammalian GAS hormonal reaction are, that 1) in Tetrahymena the level of all of the hormones studied significantly elevates under the effect of heat, osmotic or chemical stress and 2) the single stress effect is durable. It is manifested at least to the 100th generations, which means that it is inherited epigenetically. Not only hormone synthesis but the receptorial hormone binding is also elevated, which means that the whole hormonal system is activated. The stress reaction (GAS) phylogenetically can be deduced to a unicellular (Protozoan) level however, prokaryotes - which are also stress-reactive - are using another mechanisms.
- Hormone binding
- Stress hormones
ASJC Scopus subject areas
- Immunology and Microbiology(all)