Effect of stress and stress hormones on the hormone (insulin) binding of Tetrahymena.
The unicellular Tetrahymena pyriformis GL produce, store and secrete vertebrate-like hormones. In earlier experiments the effect of different stressors on the hormone levels of Tetrahymena was studied and an elevation of these was found. In the present experiments the hormone binding was investigated, using flow cytometric method. FITC-insulin binding was elevated after concentrated (5, 10, or 20 mg ml(-1)) NaCl or 0.01%, 0.1%, or 0.05% formaldehyde treatment, or after thermal stress (37 degrees C). Serotonin given together with NaCl increased and together with formaldehyde decreased the binding. Histamine always decreased the binding and insulin was indifferent. Four hours after osmotic stress, hormone binding significantly decreased and this was not influenced by hormones. However, 4 h after formaldehyde stress the binding elevated and this was further increased by repeated hormone treatments. The results show that the stress in Tetrahymena provokes an activation of its hormonal system (hormone production and binding), which is differently influenced by exogeneously given hormones.
Csaba
György
G
Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary. csagyor@net.sote.hu
Pállinger
Eva
E
D000818:Animals; D016650:Fluorescein-5-isothiocyanate; D006632:Histamine / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D013312:Stress, Physiological; D013768:Tetrahymena / Q000502:physiology*; D013997:Time Factors
D007328:Insulin; D012701:Serotonin; D006632:Histamine; D016650:Fluorescein-5-isothiocyanate