RESUMO
A decrease in nocturnal serum melatonin levels was reported in patients with clinically uncharacterized coronary artery disease. To assess whether there was a correlation between melatonin production and disease stage, we measured the nocturnal urinary excretion of 6-sulphatoxymelatonin (an index of blood melatonin concentration) in patients with chronic stable or unstable coronary disease and in a group of age-matched controls. Three groups of individuals were studied: a) 24 healthy subjects (mean age: 63 +/- 13 yr); b) 32 patients with chronic, stable, coronary disease (62 +/- 11 yr); and c) 27 patients with unstable angina (62 +/- 12 yr). For 6-sulphatoxymelatonin measurement, urine was collected from 18:00 to 06:00 hr, within 48 hr of hospitalization in the case of unstable angina. 6-Sulphatoxymelatonin was measured by a specific radioimmunoassay. Urinary 6-sulphatoxymelatonin excretion was significantly lower in unstable angina patients than in healthy subjects or in patients with stable angina. 6-Sulphatoxymelatonin correlated negatively with age in healthy subjects, but not in coronary patients. 6-Sulphatoxymelatonin excretion in patients treated with beta-adrenoceptor blockers did not differ significantly from coronary patients not receiving beta-blockers. The results indicate that patients with coronary disease have a low melatonin production rate, with greater decreases in those with higher risk of cardiac infarction and/or death.
Assuntos
Doença das Coronárias/urina , Melatonina/análogos & derivados , Melatonina/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RadioimunoensaioRESUMO
La prevalencia de microalbuminuria en los diabéticos no insulinodependientes varía entre un 8 y 43 por ciento. Su presencia se asocia a obesidad, hipertensión arterial y dislipidemia, probablemente a través de un mecanismo patogénico común: la insulinorresistencia. La microalbuminuria se ha destacado como un importante marcador de nefropatía diabética y de patologías cardiovasculares. Los diabéticos no insulinodependientes constituyen un grupo de mayor riesgo con mortalidad precoz, que deben ser tratados en forma preventiva. Entre estas medidas debe considerarse el estricto control metabólico de la diabetes, el tratamiento de la dislipidemia, obesidad e hipertensión arterial. Los inhibidores de la enzima convertidora se han demostrado eficaces en disminuir los niveles de microalbuminuria, incluso en los diabéticos no insulinodependientes normotensos