Limits...
The effects of in vivo and ex vivo various degrees of cold exposure on erythrocyte deformability and aggregation.

Erken G, Erken HA, Bor-Kucukatay M, Kucukatay V, Genc O - Med. Sci. Monit. (2011)

Bottom Line: The in vivo group was further divided into control (AR), AC (4°C, 2 hours) and ALTC (4°C, 6 hours) subgroups; and the ex vivo group was divided into control (BR) and BC (4°C, 2 hours) subgroups.Aggregation of ex vivo groups was lower compared to in vivo groups.Cold exposure at various temperatures did not cause alterations in plasma total oxidant antioxidant status and oxidative stress index (TOS, TAS, OSI) when considered together.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Faculty of Medicine, Pamukkale University, Kinikli, Denizli, Turkey. gulemmun@pau.edu.tr

ABSTRACT

Background: This study aimed to investigate alterations in hemorheology by cold exposure, in vivo and ex vivo, and to determine their relationship to oxidative stress.

Material/methods: Rats were divided into 2 in vivo and ex vivo cold exposure groups. The in vivo group was further divided into control (AR), AC (4°C, 2 hours) and ALTC (4°C, 6 hours) subgroups; and the ex vivo group was divided into control (BR) and BC (4°C, 2 hours) subgroups. Blood samples were used for the determination of erythrocyte deformability, aggregation, and oxidative stress parameters.

Results: Erythrocyte deformability and aggregation were not affected by 2-hour ex vivo cold exposure. While 2 hour in vivo cold exposure reduced erythrocyte deformability, it returned to normal after 6 hours, possibly due the compensation by acute neuroendocrine response. Six hours of cold exposure decreased aggregation index, and might be an adaptive mechanism allowing the continuation of circulation. Aggregation of ex vivo groups was lower compared to in vivo groups. Cold exposure at various temperatures did not cause alterations in plasma total oxidant antioxidant status and oxidative stress index (TOS, TAS, OSI) when considered together.

Conclusions: Results of this study indicate that the alterations observed in hemorheological parameters due to cold exposure are far from being explained by the oxidative stress parameters determined herein.

Show MeSH

Related in: MedlinePlus

Amplitude (Amp) of red blood cell (RBC) aggregation values of all groups. AR: Animal at room air, AC: Animal in cold, ALTC: Animal in long term cold, BR: Blood at room air, BC: Blood in cold. Values are expressed as means ±SE. * p<0.001, difference from group AR; ¶ p<0.05, difference from group AC; # p<0.01, difference from ALTC group.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3539619&req=5

f2-medscimonit-17-8-br209: Amplitude (Amp) of red blood cell (RBC) aggregation values of all groups. AR: Animal at room air, AC: Animal in cold, ALTC: Animal in long term cold, BR: Blood at room air, BC: Blood in cold. Values are expressed as means ±SE. * p<0.001, difference from group AR; ¶ p<0.05, difference from group AC; # p<0.01, difference from ALTC group.

Mentions: The amplitude (Amp) of RBC aggregation, which is a measure for the total extent of aggregation, is shown in Figure 2. Amp of blood at room air (BR) and blood in cold (BC) groups were decreased compared to that of animal at room air (AR, p<0.001), animal in cold (AC, p<0.05) and animal in long-term cold (ALTC, p<0.01) groups. Figure 3 shows that the aggregation index (AI) of animal in long-term cold (ALTC), blood at room air (BR) and blood in cold (BC) groups were decreased compared to animal at room air (AR) and animal in cold (AC) groups. On the other hand, the RBC aggregation half-time (t 1/2) of the blood at room air (BR) group was statistically significantly higher compared to the animal at room air (AR) and animal in cold (AC) groups (p<0.01), and the blood in cold (BC) group was higher compared to the animal in cold (AC) group (p<0.05) alone (Figure 4). The increments in Amp and AI of aggregation are in aggreement with the decrement in t 1/2 and, considered together, indicate an increase in erythrocyte aggregation.


The effects of in vivo and ex vivo various degrees of cold exposure on erythrocyte deformability and aggregation.

Erken G, Erken HA, Bor-Kucukatay M, Kucukatay V, Genc O - Med. Sci. Monit. (2011)

Amplitude (Amp) of red blood cell (RBC) aggregation values of all groups. AR: Animal at room air, AC: Animal in cold, ALTC: Animal in long term cold, BR: Blood at room air, BC: Blood in cold. Values are expressed as means ±SE. * p<0.001, difference from group AR; ¶ p<0.05, difference from group AC; # p<0.01, difference from ALTC group.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3539619&req=5

f2-medscimonit-17-8-br209: Amplitude (Amp) of red blood cell (RBC) aggregation values of all groups. AR: Animal at room air, AC: Animal in cold, ALTC: Animal in long term cold, BR: Blood at room air, BC: Blood in cold. Values are expressed as means ±SE. * p<0.001, difference from group AR; ¶ p<0.05, difference from group AC; # p<0.01, difference from ALTC group.
Mentions: The amplitude (Amp) of RBC aggregation, which is a measure for the total extent of aggregation, is shown in Figure 2. Amp of blood at room air (BR) and blood in cold (BC) groups were decreased compared to that of animal at room air (AR, p<0.001), animal in cold (AC, p<0.05) and animal in long-term cold (ALTC, p<0.01) groups. Figure 3 shows that the aggregation index (AI) of animal in long-term cold (ALTC), blood at room air (BR) and blood in cold (BC) groups were decreased compared to animal at room air (AR) and animal in cold (AC) groups. On the other hand, the RBC aggregation half-time (t 1/2) of the blood at room air (BR) group was statistically significantly higher compared to the animal at room air (AR) and animal in cold (AC) groups (p<0.01), and the blood in cold (BC) group was higher compared to the animal in cold (AC) group (p<0.05) alone (Figure 4). The increments in Amp and AI of aggregation are in aggreement with the decrement in t 1/2 and, considered together, indicate an increase in erythrocyte aggregation.

Bottom Line: The in vivo group was further divided into control (AR), AC (4°C, 2 hours) and ALTC (4°C, 6 hours) subgroups; and the ex vivo group was divided into control (BR) and BC (4°C, 2 hours) subgroups.Aggregation of ex vivo groups was lower compared to in vivo groups.Cold exposure at various temperatures did not cause alterations in plasma total oxidant antioxidant status and oxidative stress index (TOS, TAS, OSI) when considered together.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Faculty of Medicine, Pamukkale University, Kinikli, Denizli, Turkey. gulemmun@pau.edu.tr

ABSTRACT

Background: This study aimed to investigate alterations in hemorheology by cold exposure, in vivo and ex vivo, and to determine their relationship to oxidative stress.

Material/methods: Rats were divided into 2 in vivo and ex vivo cold exposure groups. The in vivo group was further divided into control (AR), AC (4°C, 2 hours) and ALTC (4°C, 6 hours) subgroups; and the ex vivo group was divided into control (BR) and BC (4°C, 2 hours) subgroups. Blood samples were used for the determination of erythrocyte deformability, aggregation, and oxidative stress parameters.

Results: Erythrocyte deformability and aggregation were not affected by 2-hour ex vivo cold exposure. While 2 hour in vivo cold exposure reduced erythrocyte deformability, it returned to normal after 6 hours, possibly due the compensation by acute neuroendocrine response. Six hours of cold exposure decreased aggregation index, and might be an adaptive mechanism allowing the continuation of circulation. Aggregation of ex vivo groups was lower compared to in vivo groups. Cold exposure at various temperatures did not cause alterations in plasma total oxidant antioxidant status and oxidative stress index (TOS, TAS, OSI) when considered together.

Conclusions: Results of this study indicate that the alterations observed in hemorheological parameters due to cold exposure are far from being explained by the oxidative stress parameters determined herein.

Show MeSH
Related in: MedlinePlus