Abstract
Changes in cardiac myosin isozymes and serum thyroid hormone levels were investigated in rats following 10 Gy whole-body gamma irradiation. The percent β-myosin heavy chain increased from 21.3 ± 1.8 to 28.1 ± 6.8 (NS) at 3-day postirradiation, 37.7 ± 1.9 (P<.001) at 6-day postirradiation, and 43.8 ± 3.3 (P<.001) at 9-day postirradiation. Along with the change in myosin isozymes was a significant 53% decrease (P<.001) in the serum thyroxine (T4) level by day 3 postirradiation, remaining depressed through day 9 postirradiation. The serum 3,5,3′-triiodothyronine (T3) level, however, was normal until day 9, when significant depression was also observed. In contrast, the thyroid-stimulating hormone (TSH) level was significantly increased by fourfold at day 3, returning to near normal values by day 9 postirradiation. Daily injections of physiological doses of T3 ( 0.3 μg 100 g body weight) prevented the change in the myosin isozymes following whole-body irradiation. Daily pharmacological injections of T3 ( 3.0 μg 100 g body weight) to the irradiated rats produced a further decrease in the percent β-myosin heavy chain (below control values) indicating tissue hyperthyroidism. Thus, this study suggests that the change in myosin isozymes following whole-body irradiation is caused by an alteration in thyroid hormone activity.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 64-68 |
| Number of pages | 5 |
| Journal | Metabolism |
| Volume | 39 |
| Issue number | 1 |
| DOIs | |
| State | Published - 1990 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Endocrinology
- Endocrinology, Diabetes and Metabolism
Cite this
Alterations in rat cardiac myosin isozymes induced by whole-body irradiation are prevented by 3,5,3′-l-triiodothyronine. / Litten, Raye Z.; Fein, Henry G.; Gainey, Grealon T.; Walden, Thomas L.; Smallridge, Robert Christian.
In: Metabolism, Vol. 39, No. 1, 1990, p. 64-68.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Alterations in rat cardiac myosin isozymes induced by whole-body irradiation are prevented by 3,5,3′-l-triiodothyronine
AU - Litten, Raye Z.
AU - Fein, Henry G.
AU - Gainey, Grealon T.
AU - Walden, Thomas L.
AU - Smallridge, Robert Christian
PY - 1990
Y1 - 1990
N2 - Changes in cardiac myosin isozymes and serum thyroid hormone levels were investigated in rats following 10 Gy whole-body gamma irradiation. The percent β-myosin heavy chain increased from 21.3 ± 1.8 to 28.1 ± 6.8 (NS) at 3-day postirradiation, 37.7 ± 1.9 (P<.001) at 6-day postirradiation, and 43.8 ± 3.3 (P<.001) at 9-day postirradiation. Along with the change in myosin isozymes was a significant 53% decrease (P<.001) in the serum thyroxine (T4) level by day 3 postirradiation, remaining depressed through day 9 postirradiation. The serum 3,5,3′-triiodothyronine (T3) level, however, was normal until day 9, when significant depression was also observed. In contrast, the thyroid-stimulating hormone (TSH) level was significantly increased by fourfold at day 3, returning to near normal values by day 9 postirradiation. Daily injections of physiological doses of T3 ( 0.3 μg 100 g body weight) prevented the change in the myosin isozymes following whole-body irradiation. Daily pharmacological injections of T3 ( 3.0 μg 100 g body weight) to the irradiated rats produced a further decrease in the percent β-myosin heavy chain (below control values) indicating tissue hyperthyroidism. Thus, this study suggests that the change in myosin isozymes following whole-body irradiation is caused by an alteration in thyroid hormone activity.
AB - Changes in cardiac myosin isozymes and serum thyroid hormone levels were investigated in rats following 10 Gy whole-body gamma irradiation. The percent β-myosin heavy chain increased from 21.3 ± 1.8 to 28.1 ± 6.8 (NS) at 3-day postirradiation, 37.7 ± 1.9 (P<.001) at 6-day postirradiation, and 43.8 ± 3.3 (P<.001) at 9-day postirradiation. Along with the change in myosin isozymes was a significant 53% decrease (P<.001) in the serum thyroxine (T4) level by day 3 postirradiation, remaining depressed through day 9 postirradiation. The serum 3,5,3′-triiodothyronine (T3) level, however, was normal until day 9, when significant depression was also observed. In contrast, the thyroid-stimulating hormone (TSH) level was significantly increased by fourfold at day 3, returning to near normal values by day 9 postirradiation. Daily injections of physiological doses of T3 ( 0.3 μg 100 g body weight) prevented the change in the myosin isozymes following whole-body irradiation. Daily pharmacological injections of T3 ( 3.0 μg 100 g body weight) to the irradiated rats produced a further decrease in the percent β-myosin heavy chain (below control values) indicating tissue hyperthyroidism. Thus, this study suggests that the change in myosin isozymes following whole-body irradiation is caused by an alteration in thyroid hormone activity.
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UR - http://www.scopus.com/inward/citedby.url?scp=0025190379&partnerID=8YFLogxK
U2 - 10.1016/0026-0495(90)90149-7
DO - 10.1016/0026-0495(90)90149-7
M3 - Article
C2 - 2136761
AN - SCOPUS:0025190379
VL - 39
SP - 64
EP - 68
JO - Metabolism: Clinical and Experimental
JF - Metabolism: Clinical and Experimental
SN - 0026-0495
IS - 1
ER -