A role for thyroid hormones in cold-induced elevation of blood pressure and cardiac hypertrophy

1994 ◽  
Vol 72 (9) ◽  
pp. 1066-1074 ◽  
Author(s):  
Melvin J. Fregly ◽  
Fabian Rossi ◽  
J. Robert Cade

The systolic blood pressures of two groups of rats that were exposed to cold (5 °C) for 4 weeks were elevated significantly above that of warm-acclimated controls maintained at 24 °C. At this time these groups were given the antithyroid drug aminotriazole in their food at 0.3 g/kg. At the same time, one group was given 15.8 μg thyroxine (T4)/kg body mass per day, while the second received 31.6. The doses were chosen as replacement (15.8 μg/kg) and twice replacement (31.8 μg/kg) for the rats. The results of the study revealed that both groups receiving aminotriazole and T4 had reductions in blood pressure within 1 week of initiation of treatment. Blood pressures reached control level after 5 weeks. Cardiac hypertrophy accompanying cold-induced hypertension was reduced with the lower dose of T4 and prevented with the higher dose. Serum concentrations of T4 and triiodothyronine (T3) in the two treated groups were reduced, while serum thyroid-stimulating hormone concentration and thyroid mass were increased above that of the warm-acclimated control group. This suggests that the rats were hypothyroid relative to the warm-acclimated control group. However, the treated rats grew at the same rate as nontreated, cold-exposed controls and had similar food and water intakes, a similar dipsogenic response to acute administration of isoproterenol, and similar colonic temperatures. These measurements suggest that the rats were not functionally hypothyroid. Nevertheless, the results suggest that a paradigm in which the secretory ability of the thyroid gland is blocked, and T4 is returned at a constant, albeit suboptimal, level, reduced blood pressure and cardiac hypertrophy in cold-exposed rats. Hence, the increased turnover of thyroid hormones that characteristically accompanies exposure to cold plays a role in these changes. These studies also indicate that an increase in the rate of secretion of T4 is not required for survival in cold air.Key words: cold-induced hypertension, thyroxine, triiodothyronine, thyroid-stimulating hormone, aminotriazole, antithyroid drug, blood pressure, cardiac hypertrophy, catecholamines, norepinephrine, epinephrine, dopamine.

Author(s):  
SALOME GLONTI ◽  
RUSUDAN VADACHKORIA ◽  
JUMBER UNGIADZE

The Breast Benign tumor (BBT) is currently considered a significant breast health problem within women of all ages. In the present study, we aimed to investigate the Tumor markers CA125 and CA153, thyroid hormones free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), and vitamin D within benign breast tumor (BBT) during the reproduction ages. Twenty patients (ten patients in the control group and ten patients in cases (Breast Benign Tumor); Notably, the studies confirm the decrease in FT4 and FT3 and increase of the thyroid-stimulating hormone (TSH). In addition, the decreased level of Vitamin D is also revealed in BBT.


2021 ◽  
Vol 53 (04) ◽  
pp. 272-279
Author(s):  
Chaochao Ma ◽  
Xiaoqi Li ◽  
Lixin Liu ◽  
Xinqi Cheng ◽  
Fang Xue ◽  
...  

AbstractThyroid hormone reference intervals are crucial for diagnosing and monitoring thyroid dysfunction during early pregnancy, and the dynamic change trend of thyroid hormones during pregnancy can assist clinicians to assess the thyroid function of pregnant women. This study aims to establish early pregnancy related thyroid hormones models and reference intervals for pregnant women. We established two derived databases: derived database* and derived database#. Reference individuals in database* were used to establish gestational age-specific reference intervals for thyroid hormones and early pregnancy related thyroid hormones models for pregnant women. Individuals in database# were apparently healthy non-pregnant women. The thyroid hormones levels of individuals in database# were compared with that of individuals in database* using nonparametric methods and the comparative confidence interval method. The differences in thyroid stimulating hormone and free thyroxine between early pregnant and non-pregnant women were statistically significant (p<0.0001). The reference intervals of thyroid stimulating hormone, free thyroxine and free triiodothyronine for early pregnant women were 0.052–3.393 μIU/ml, 1.01–1.54 ng/dl, and 2.51–3.66 pg/ml, respectively. Results concerning thyroid stimulating hormone and free thyroxine reference intervals of early pregnancy are comparable with those from other studies using the same detection platform. Early pregnancy related thyroid hormones models showed various change patterns with gestational age for thyroid hormones. Early pregnancy related thyroid hormones models and reference intervals for pregnant women were established, so as to provide accurate and reliable reference basis for the diagnosing and monitoring of maternal thyroid disfunction in early pregnancy.


2018 ◽  
Vol 7 (2) ◽  
pp. 116
Author(s):  
Budi Darmawan ◽  
Diyah Fatmasari ◽  
Rr. Sri Endang Pujiast

Background: Wet cupping, furthermore mentioned cupping, decreases blood pressures through the level of negative air pressures added by hydrostatics filtration pressure to reinforce the power of fluids filtration in capillaries. However, an appropriate negative air pressure to decrease blood pressure remains an uncertainty.Purpose: This study aimed to analyze negative air pressure differences on cupping in decreasing blood pressures in hypertensive patients.Methods: This is a quasi-experimental design conducted in three Community Health Centers in Langsa City, Aceh, Indonesia. The samples were 36 hypertensive males with age from 45 to 55, who were randomly stratified into two groups with cupping pressures 400 mbar (n=18) as the control group; and 540 mbar (n=18) as the intervention group. The cupping session was performed to each group on T1 (alkahil) point and in the middle line of both shoulders blade points. The systolic blood pressure (SBP) and diastolic blood pressures (DBP) were measured by validated automatic sphygmomanometer. The follow-up periods were one week and two weeks. The data were then analyzed by repeated measures ANOVA.Results: Cupping pressure of 400 mbar decreased the mean of SBP and DPB with a p-value of 0.450 and 0.026, respectively after two weeks of intervention. Meanwhile, cupping pressure of 540 mbar decreased the mean of SBP and DBP with a p-value of 0.006 and 0.057, respectively. Tests of within-subjects resulted in the p-value of 0.250 (SBP) and 0.176 (DBP) after two weeks of intervention. There were no significant differences in SBP and DBP between the intervention group and the control group.Conclusion: The cupping pressure between 400 mbar and 540 mbar could reduce blood pressure; however, the cupping pressure of 540 mbar yielded greater effect in decreasing blood pressure than the 400 mbar. Negative air vacuum pressure loads on cupping to decrease blood pressure should be considered between 400 to 540 mbar, and further studies are needed.


Hypertension ◽  
2020 ◽  
Vol 76 (Suppl_1) ◽  
Author(s):  
Xiao C Li ◽  
Ana P Leite ◽  
Liang Zhang ◽  
Jia L Zhuo

The present study tested the hypothesis that intratubular angiotensin II (Ang II) and AT 1a receptors in the proximal tubules of the kidney plays an important role in basal blood pressure control and in the development of Ang II-induced hypertension. Mutant mice with proximal tubule-specific deletion of AT 1a receptors in the kidney, PT- Agtr1a -/- , were generated to test the hypothesis. Eight groups (n=7-12 per group) of adult male wild-type (WT) and PT- Agtr1a -/- mice were infused with or without Ang II for 2 weeks (1.5 mg/kg, i.p.). Basal systolic, diastolic, and mean arterial pressures were ~13 ± 3 mmHg lower in PT- Agtr1a -/- than WT mice ( P <0.01). Basal glomerular filtration rate (GFR), as measured using transdermal FITC-sinistrin, was significantly higher in PT- Agtr1a -/- mice (WT: 160.4 ± 7.0 μl/min vs. PT- Agtr1a -/- : 186.0 ± 6.0 μl/min, P <0.05). Basal 24 h urinary Na + excretion (U Na V) was significantly higher in PT- Agtr1a -/- than WT mice ( P <0.01). In response to Ang II infusion, both WT and PT- Agtr1a -/- mice developed hypertension, and the magnitude of the pressor response to Ang II was similar in WT (Δ43 ± 3 mmHg, P <0.01) and PT- Agtr1a -/- mice (Δ39 ± 5 mmHg, P <0.01). However, the absolute blood pressure level was still 16 ± 3 mmHg lower in PT- Agtr1a -/- mice ( P <0.01). Ang II significantly decreased GFR to 132.2 ± 7.0 μl/min in WT mice ( P <0.01), and to 129.4 ± 18.6 μl/min in PT- Agtr1a -/- mice ( P <0.01), respectively. In WT mice, U Na V increased from 139.3 ± 22.3 μmol/24 h in the control group to 196.4 ± 29.6 μmol/24 h in the Ang II-infused group ( P <0.01). In PT- Agtr1a -/- mice, U Na V increased from 172.0 ± 10.2 μmol/24 h in the control group to 264.7 ± 35.4 μmol/24 h in the Ang II-infused group ( P <0.01). The pressor response to Ang II was attenuated, while the natriuretic response was augmented by losartan in WT and PT- Agtr1a -/- mice ( P <0.01). Finally, proximal tubule-specific deletion of AT 1a receptors significantly augmented the pressure-natriuresis response and natriuretic responses to acute saline infusion ( P <0.01) or a 2% high salt diet ( P <0.01). We concluded that deletion of AT 1a receptors selectively in the proximal tubules lowers basal blood pressure and attenuates Ang II-induced hypertension by increasing GFR and promoting the natriuretic response in PT- Agtr1a -/- mice.


1992 ◽  
Vol 15 (10) ◽  
pp. 585-589 ◽  
Author(s):  
M. Yeksan ◽  
N. Tamer ◽  
M. Cirit ◽  
S. Türk ◽  
G. Akhan ◽  
...  

The aim of this study was to evaluate the effect of r-HuEPO treatment on free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulating hormone (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), free testosterone and prolactin levels in uremic hemodialysis patients. Twenty-four uremic hemodialysis patients were given r-HuEPO with a dose 60 U/kg as intravenous bolus injection at the end of each dialysis session. Once the hematocrit value of the patient had reached a range of 30-35%, the dose was adjusted so as to keep the hematocrit levels constant. Twenty uremic dialysis patients were taken as control group. The above-mentioned hormone levels of patients and control group were determined before and 4 months after r-HuEPO treatment. After the treatment, serum prolactin levels significantly decreased in both sexes (36.8 ± 7.8 vs 22.9 ± 6.3 ng/ml and 78.3 ±13.3 vs 37.4 ± 10.4 ng/ml male and female, respectively). FT3 and FT4 significantly increased (1.17 vs 1.67 pg/ml, p<0.05, and 0.64 vs 0.084 ng/dl, p<0.05, respectively). TSH levels increased but those changes were not significant. There was no change in the level of any hormone in the control group. Also, the sexual functions of eight male patients treated with r-HuEPO improved and menstruation started again in four female patients. We concluded that r-HuEPO treatment especially decreases prolactin level in uremic hemodialysis patients. It is conceivable that correction of elevated prolactin levels could improve sexual disorders in these patients.


2019 ◽  
Vol 317 (2) ◽  
pp. F254-F263
Author(s):  
Anne D. Thuesen ◽  
Stine H. Finsen ◽  
Louise L. Rasmussen ◽  
Ditte C. Andersen ◽  
Boye L. Jensen ◽  
...  

T-type Ca2+ channel Cav3.1 promotes microvessel contraction ex vivo. It was hypothesized that in vivo, functional deletion of Cav3.1, but not Cav3.2, protects mice against angiotensin II (ANG II)-induced hypertension. Mean arterial blood pressure (MAP) and heart rate were measured continuously with chronically indwelling catheters during infusion of ANG II (30 ng·kg−1·min−1, 7 days) in wild-type (WT), Cav3.1−/−, and Cav3.2−/− mice. Plasma aldosterone and renin concentrations were measured by radioimmunoassays. In a separate series, WT mice were infused with ANG II (100 ng·kg−1·min−1) with and without the mineralocorticoid receptor blocker canrenoate. Cav3.1−/− and Cav3.2−/− mice exhibited no baseline difference in MAP compared with WT mice, but day-night variation was blunted in both Cav3.1 and Cav3.2−/− mice. ANG II increased significantly MAP in WT, Cav3.1−/−, and Cav3.2−/− mice with no differences between genotypes. Heart rate was significantly lower in Cav3.1−/− and Cav3.2−/− mice compared with control mice. After ANG II infusion, plasma aldosterone concentration was significantly lower in Cav3.1−/− compared with Cav3.2−/− mice. In response to ANG II, fibrosis was observed in heart sections from both WT and Cav3.1−/− mice and while cardiac atrial natriuretic peptide mRNA was similar, the brain natriuretic peptide mRNA increase was mitigated in Cav3.1−/− mice ANG II at 100 ng/kg yielded elevated pressure and an increased heart weight-to-body weight ratio in WT mice. Cardiac hypertrophy, but not hypertension, was prevented by the mineralocorticoid receptor blocker canrenoate. In conclusion, T-type channels Cav3.1and Cav3.2 do not contribute to baseline blood pressure levels and ANG II-induced hypertension. Cav3.1, but not Cav3.2, contributes to aldosterone secretion. Aldosterone promotes cardiac hypertrophy during hypertension.


1972 ◽  
Vol 136 (2) ◽  
pp. 318-330 ◽  
Author(s):  
Lewis K. Dahl ◽  
George Leitl ◽  
Martha Heine

Among genetically hypertension-prone rats, dietary sodium (chloride) was demonstrably hypertensinogenic and potassium (chloride) antihypertensinogenic. On diets containing the same NaCl but different KCl concentrations, mean blood pressure was greater in rats receiving less dietary potassium, i.e., diets with a higher Na/K molar ratio. On diets with different absolute concentrations of NaCl and KCl, but the same Na/K molar ratios, rats on the higher absolute NaCl intakes had the higher blood pressures. On diets with different absolute concentrations of NaCl and KCl, and different Na/K molar ratios, a group on a lower absolute NaCl intake but with a higher Na/K ratio could have more hypertension than a group on a higher absolute NaCl intake but with a lower Na/K ratio. At equivalent molar ratios, the respective effects of these two ions on blood pressure were dominated by that of sodium. It was concluded that the dietary Na/K molar ratio can be an important determinant for the severity, or even development, of salt-induced hypertension. The mechanism of the moderating effect of potassium on sodium-induced hypertension was unclear.


2019 ◽  
Vol 25 (1) ◽  
Author(s):  
Meruyert Massabayeva ◽  
Nailya Chaizhunusova ◽  
Nurlan Aukenov ◽  
Tolkyn Bulegenov ◽  
Bakytbek Apsalikov ◽  
...  

Abstract Background To study the association of radiation risk in the 2nd –3rd generations with polymorphisms in the genes CYP1A1, CYP2E1, GSTP1 and changes in the thyroid. Methods 5 polymorphic gene variants (rs1048943, rs4646421, rs2070676, rs3813867, rs1695) were studied in 399 people living in the East Kazakhstan region in this research. 248 people of the 2nd - 3rd generation lived in the territory with radiation exposure in Abai, Borodulikha areas, and 151 people the comparison group lived in Kurchum district without radiation exposure comparable in sex and age with control group. Results The results show that there is a significant association of rs1048943 in exposed and unexposed groups (p < 0.003), and the absence of association of rs4646421, rs2070676, rs3813867, rs1695 in the studied groups. The mean value of thyroxine in carriers of the AG + GG genotype of rs4646421 is significantly lower than in AA genotype carriers (p = 0.04); no significant changes were found in genotypes’ distribution with thyroid-stimulating hormone and anti-thyroid peroxidase indicators. Significant changes were in levels of anti-thyroid peroxidase between exposed and unexposed groups (p = 0.007). The thyroxine - thyroid-stimulating hormone levels were not significantly different in exposed and unexposed groups (p > 0.3). Conclusions This study demonstrated the association of rs1048943 polymorphism with living in the radiation zone in the 2nd and 3rd generations for the first time. Thyroxine levels decrease was identified in the 2nd and 3rd generation residents of the exposed area, as well as a significant increase of anti-thyroid peroxidase occurs in individuals of the 2nd and 3rd generation living in areas with radiation exposure.


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