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Testosterone Replacement Therapy Prevents Alterations of Coronary Vascular Reactivity Caused by Hormone Deficiency Induced by Castration.

Rouver WN, Delgado NT, Menezes JB, Santos RL, Moyses MR - PLoS ONE (2015)

Bottom Line: Furthermore, castration modulated the lipid and hormonal profiles and decreased body weight, and testosterone therapy restored all of these parameters.Our results revealed an increase in SBP in the SUPRA group.In addition, our data led us to conclude that physiological concentrations of testosterone may play a beneficial role in the cardiovascular system by maintaining an environment that is favourable for the activity of an endothelium-dependent vasodilator without increasing SBP.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiological Sciences, Federal University of Espírito Santo (Universidade Federal do Espírito Santo-UFES), Vitória, Brazil.

ABSTRACT
The present study aimed to determine the effects of chronic treatment with different doses of testosterone on endothelium-dependent coronary vascular reactivity in male rats. Adult male rats were divided into four experimental groups: control (SHAM), castrated (CAST), castrated and immediately treated subcutaneously with a physiological dose (0.5 mg/kg/day, PHYSIO group) or supraphysiological dose (2.5 mg/kg/day, SUPRA group) of testosterone for 15 days. Systolic blood pressure (SBP) was assessed at the end of treatment through tail plethysmography. After euthanasia, the heart was removed and coronary vascular reactivity was assessed using the Langendorff retrograde perfusion technique. A dose-response curve for bradykinin (BK) was constructed, followed by inhibition with 100 μM L-NAME, 2.8 μM indomethacin (INDO), L-NAME + INDO, or L-NAME + INDO + 0.75 μM clotrimazole (CLOT). We observed significant endothelium-dependent, BK-induced coronary vasodilation, which was abolished in the castrated group and restored in the PHYSIO and SUPRA groups. Furthermore, castration modulated the lipid and hormonal profiles and decreased body weight, and testosterone therapy restored all of these parameters. Our results revealed an increase in SBP in the SUPRA group. In addition, our data led us to conclude that physiological concentrations of testosterone may play a beneficial role in the cardiovascular system by maintaining an environment that is favourable for the activity of an endothelium-dependent vasodilator without increasing SBP.

No MeSH data available.


Related in: MedlinePlus

Hormone level.Testosterone in the SHAM (n = 15), CAST (n = 15); PHYSIO (n = 17), and SUPRA (n = 16) groups. Data are expressed as the mean ± SEM. * p<0.05 compared with the SHAM group, #p<0.05 compared with the CAST group, and +p<0.05 compared with the PHYSIO group.
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pone.0137111.g004: Hormone level.Testosterone in the SHAM (n = 15), CAST (n = 15); PHYSIO (n = 17), and SUPRA (n = 16) groups. Data are expressed as the mean ± SEM. * p<0.05 compared with the SHAM group, #p<0.05 compared with the CAST group, and +p<0.05 compared with the PHYSIO group.

Mentions: By analysing the hormonal profile (Fig 4), we confirmed that castration was effective in significantly decreasing testosterone levels in the castrated group (SHAM, 314 ± 31 ng/dL; CAST, 4 ± 1 ng/dL). In addition, treatment with a physiological dose of testosterone (325 ± 69 ng/dL) was effective in maintaining a testosterone level similar to that observed in the SHAM group. On the other hand, the SUPRA group exhibited a marked increase in testosterone levels (1,385 ± 71.1 ng/dL).


Testosterone Replacement Therapy Prevents Alterations of Coronary Vascular Reactivity Caused by Hormone Deficiency Induced by Castration.

Rouver WN, Delgado NT, Menezes JB, Santos RL, Moyses MR - PLoS ONE (2015)

Hormone level.Testosterone in the SHAM (n = 15), CAST (n = 15); PHYSIO (n = 17), and SUPRA (n = 16) groups. Data are expressed as the mean ± SEM. * p<0.05 compared with the SHAM group, #p<0.05 compared with the CAST group, and +p<0.05 compared with the PHYSIO group.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556439&req=5

pone.0137111.g004: Hormone level.Testosterone in the SHAM (n = 15), CAST (n = 15); PHYSIO (n = 17), and SUPRA (n = 16) groups. Data are expressed as the mean ± SEM. * p<0.05 compared with the SHAM group, #p<0.05 compared with the CAST group, and +p<0.05 compared with the PHYSIO group.
Mentions: By analysing the hormonal profile (Fig 4), we confirmed that castration was effective in significantly decreasing testosterone levels in the castrated group (SHAM, 314 ± 31 ng/dL; CAST, 4 ± 1 ng/dL). In addition, treatment with a physiological dose of testosterone (325 ± 69 ng/dL) was effective in maintaining a testosterone level similar to that observed in the SHAM group. On the other hand, the SUPRA group exhibited a marked increase in testosterone levels (1,385 ± 71.1 ng/dL).

Bottom Line: Furthermore, castration modulated the lipid and hormonal profiles and decreased body weight, and testosterone therapy restored all of these parameters.Our results revealed an increase in SBP in the SUPRA group.In addition, our data led us to conclude that physiological concentrations of testosterone may play a beneficial role in the cardiovascular system by maintaining an environment that is favourable for the activity of an endothelium-dependent vasodilator without increasing SBP.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiological Sciences, Federal University of Espírito Santo (Universidade Federal do Espírito Santo-UFES), Vitória, Brazil.

ABSTRACT
The present study aimed to determine the effects of chronic treatment with different doses of testosterone on endothelium-dependent coronary vascular reactivity in male rats. Adult male rats were divided into four experimental groups: control (SHAM), castrated (CAST), castrated and immediately treated subcutaneously with a physiological dose (0.5 mg/kg/day, PHYSIO group) or supraphysiological dose (2.5 mg/kg/day, SUPRA group) of testosterone for 15 days. Systolic blood pressure (SBP) was assessed at the end of treatment through tail plethysmography. After euthanasia, the heart was removed and coronary vascular reactivity was assessed using the Langendorff retrograde perfusion technique. A dose-response curve for bradykinin (BK) was constructed, followed by inhibition with 100 μM L-NAME, 2.8 μM indomethacin (INDO), L-NAME + INDO, or L-NAME + INDO + 0.75 μM clotrimazole (CLOT). We observed significant endothelium-dependent, BK-induced coronary vasodilation, which was abolished in the castrated group and restored in the PHYSIO and SUPRA groups. Furthermore, castration modulated the lipid and hormonal profiles and decreased body weight, and testosterone therapy restored all of these parameters. Our results revealed an increase in SBP in the SUPRA group. In addition, our data led us to conclude that physiological concentrations of testosterone may play a beneficial role in the cardiovascular system by maintaining an environment that is favourable for the activity of an endothelium-dependent vasodilator without increasing SBP.

No MeSH data available.


Related in: MedlinePlus