RESUMO
BACKGROUND: The Endothelin-1 (ET-1) is a powerful vasoconstrictor peptide produced by endothelial cells in many vascular diseases probably as a response to vessel damage. In hyperthyroidism as in other endocrinological diseases elevated ET-1 plasma levels have been found. METHODS: The effect of antithyroid therapy on ET-1 plasmatic levels was evaluated by measuring ET-1 plasma levels before and 2 and 6 months after treatment with methimazole in 14 patients affected by hyperthyroidism. RESULTS: The hyperthyroid patients had significantly higher ET-1 levels than the controls (18.85 +/- 5.7 vs 10.9 +/- 2.1 pg/ml), while after treatment no difference was found. The ET-1 plasma levels of hyperthyroid patients correlated closely with the raised thyroid metabolic activity independently of its cause. It is possible that the increased ET-1 levels in hyperthyroid patients are the expression of blood vessel damage caused by high thyroid hormone levels. CONCLUSIONS: Moreover the results of this study could suggest that, in future, ET-1 plasmatic levels might be considered as a functional thyroid index in hyperthyroid diseases.
Assuntos
Endotelina-1/sangue , Hipertireoidismo/sangue , Adulto , Biomarcadores/sangue , Feminino , Doença de Graves/sangue , Humanos , Hipertireoidismo/tratamento farmacológico , Masculino , Fatores SexuaisRESUMO
In diabetics, vascular examination may consider great and medium arteries and microcirculation. The aim of this study is correlation between stenosis in carotid and femoral bifurcation, ultrasound biopsy, and laser-Doppler measurements of distal microcirculation in diabetics. During a six month period, we have examined 90 diabetics in the diabetological service of the Civita Castellana Hospital (Viterbo, Italy), asymptomatic for any vascular distal, cerebral or coronary disease. Subjects were 49 +/- 20 years old with 15 +/- 5 years of diabetes; glycosilate haemoglobin was 7% (mean). 70% of diabetics (62% type I, 38% type II) had an altered veno-arteriolar reflex and 30% of these an ultrasound biopsy value of more than 25. These data demonstrate that most diabetic subjects develop an early, preclinical neuropathy that is directly proportional to the arterial wall condition.
Assuntos
Circulação Sanguínea , Diabetes Mellitus/fisiopatologia , Adulto , Idoso , Arteriopatias Oclusivas/fisiopatologia , Arteriosclerose/fisiopatologia , Estenose das Carótidas/fisiopatologia , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Neuropatias Diabéticas/etiologia , Feminino , Artéria Femoral/fisiopatologia , Humanos , Fluxometria por Laser-Doppler , Masculino , Microcirculação , Pessoa de Meia-IdadeRESUMO
3',5'-adenosine monophosphate (cAMP), adenylate cyclase and cAMP-phosphodiesterase (PDE) activity were measured in aorta homogenates from normal and spontaneously hypertensive rats (SHR) during treatment with prazosin, an antihypertensive drug. cAMP levels were lower in SHR than in normal rats. In SHR prazosin treatment induced marked inhibition of PDE activity thus causing an increase in cAMP levels; adenylate cyclase activity remained unaffected. This effect was only present for the first 32 days of drug administration.