Cold-stress induces thymocyte apoptosis in the rat Seiji Morishita, Yasuaki Nishi, Eisuke F Sato, Kiyonori Yamaoka, Masanobu Manabe, Masayasu Inoue  Pathophysiology  Volume 4, Issue 3, Pages 213-219 (September 1997) DOI: 10.1016/S0928-4680(97)00021-7

Fig. 1 Effect of cold temperature on blood glucose and corticosterone. Animals were put in a cold room (5°C) for 4 h. During the exposure to cold, changes in the body temperature (a), blood glucose (b) and corticosterone levels (c) were determined as described in the text. Values show the mean±S.D. derived from four to nine animals. Open circles, fed rats; closed circles, 24 h fasted group. *P<0.05 Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 2 Changes of thymus weight and total number of thymocytes. At the indicated times after exposure to cold temperature (5°C), thymuses were excised and their weight were measured. The number of total thymocytes was also counted. Data show mean±S.E. derived from three animals (*P<0.05). Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 3 Histological analysis of the thymus. Specimens of the thymus were stained either with hematoxylin/eosin (a, b) or with ApopTag kit (c, d). The thymus from control rats, a and c; the thymus from animals exposed to cold temperature for 4 h, b and d. Magnification ×400. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 4 Effect of cold-stress on thymocyte DNA. After fasting for 24 h, animals were exposed to cold temperature for 0 (lane 2), 2 (lane 3), 4 (lane 4) and 8 h (lane 5). Then, DNA samples were obtained from thymocytes and subjected to agarose gel electrophoresis as described in the text. Data show one typical results of three separate experiments. Lane 1 and 6, molecular weight markers. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 5 Effect of RU486 on the fragmentation of thymocyte DNA induced by cold-stress. Animals were intraperitoneally administered 1 ml of either saline (control) or 20 mg/kg of RU486 30 min before the experiments. After exposure to cold temperature for 4 h, DNA samples were extracted from thymocytes of these animals and subjected to agarose gel electrophoresis. Lane 1, molecular weight markers; lane 2, thymocyte DNA from control animal; lane 3, DNA sample from the rat exposed to cold temperature; lane 4, RU486-treated and exposed to cold temperature. Other conditions were as in Fig. 4. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 6 Effect of adrenalectomy on the fragmentation of thymocyte DNA induced by cold-stress. Animals were fasted for 24 h. After exposure to either room temperature (lane 2, 3, 4) or 5°C (lane 5, 6, 7) for 4 h, DNA samples were extracted from thymocytes of intact (lane 2 and 5), sham operated (lane 3 and 6) or adrenalectomized rats (lane 4 and 7). Other conditions were as in Fig. 4. Lane 1 and 8, molecular weight markers. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 7 Effect of feeding on the fragmentation of thymocyte DNA induced by cold-stress. Four hours after exposure to cold temperature, DNA samples were extracted from thymocytes of fed (lane 4) or 24 h fasted rats (lane 3). Other conditions were as in Fig. 4. Lane 1 and 5, molecular weight markers; lane 2, thymocyte DNA from control rat; lane 4, fed+cold-stress. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 8 Effect of glucose and 3-O-methyl-d-glucose on the fragmentation of thymocyte DNA. Animals were orally administered either 3 ml water (lane 2 and 3), 7.5 g/kg glucose (lane 4) or 3-O-methyl-d-glucose (lane 5) 30 min before the experiments. Then, they were exposed to cold temperature for 4 h and DNA samples were extracted from thymocytes (lane 3, 4, 5). Lane 1, DNA sample from control rats; lane 2, +water; lane 6, molecular weight markers. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)

Fig. 9 Effect of glucose-loading on the change in plasma corticosterone levels. Animals were orally administered 7.5 g/kg glucose 15 min before the experiments. After exposure to cold temperature for 4 h, plasma levels of corticosterone were determined. Data show mean±S.D. derived from 4–9 animals. Open circles, control group; closed circles, glucose-loaded group. *P<0.05. Pathophysiology 1997 4, 213-219DOI: (10.1016/S0928-4680(97)00021-7)