RESUMEN
To increase our knowledge on the effects of previous and current physical activity on cardiovascular health, we studied a group of Finnish male former elite athletes (endurance, n = 49; power, n = 50) and their 49 age and area-matched controls, aged 64-89 years. Body mass index (BMI), fasting serum glucose, lipids, blood pressure, and ultrasonography of cardiac and carotid artery structure and function were measured. Former endurance athletes smoked less, had lower prevalence of hypertension, and had higher intensity and volume of leisure time physical activity (LTPA) than the controls. No difference was detected in cardiac or carotid artery structure and function between these groups. Former athletes performing high-intensity LTPA were slightly younger (possible selection bias), had lower BMI and waist circumference, lower use of antihypertensives, lower prevalence of diabetes, lower pulse wave velocity, and higher carotid artery elasticity than former athletes not performing high-intensity LTPA. In conclusion, former athletes had a higher intensity and volume of LTPA than the controls. Athletes performing vigorous LTPA had more elastic arteries than athletes performing moderately or no LTPA. Vigorous LTPA through the whole lifetime associates with good cardiovascular health, although the previous medical history may play an important role.
Asunto(s)
Diabetes Mellitus/epidemiología , Ejercicio Físico/fisiología , Hipercolesterolemia/epidemiología , Hipertensión/epidemiología , Esfuerzo Físico/fisiología , Deportes/fisiología , Anciano , Anciano de 80 o más Años , Glucemia/metabolismo , Presión Sanguínea , Índice de Masa Corporal , Grosor Intima-Media Carotídeo , Ecocardiografía , Finlandia/epidemiología , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Análisis de la Onda del Pulso , Rigidez Vascular , Circunferencia de la CinturaRESUMEN
The purpose of this study was to investigate the expression of the EGF family of growth factors and EGF receptor subtypes (ErbB1-4) present in lacrimal gland and determine the effects of these growth factors on different functions of rat lacrimal gland. RT-PCR was used to detect mRNA expression in the lacrimal gland of selected members of the EGF family of growth factors, namely EGF, transforming growth factor alpha (TGF-alpha), heparin-binding EGF (HB-EGF), and heregulin. The presence of ErbB receptors was investigated by immunofluorescence microscopy and western blot analysis. The effects of EGF, TGF-alpha, HB-EGF, and heregulin on protein secretion from lacrimal gland acini were examined using a fluorescent assay for peroxidase, a marker of protein secretion. Fura-2 tetra-acetoxymethyl ester was used to measure the effects of the growth factors on intracellular [Ca2+] ([Ca2+]i) in acini. MAPK activation in acini by these growth factors was also examined by western blot analysis using antibodies specific to phosphorylated p42/44 MAPK and total p42 MAPK. Rat lacrimal gland expressed EGF, TGF-alpha, HB-EGF, and heregulin mRNA, and all four ErbB receptors were present in the lacrimal gland as detected by western blot analyses. ErbB 1 and ErbB2 were located in basal and lateral membranes of acinar and ductal cells. The location of ErbB3 could not be determined while ErbB4 was found in ductal cells. Heregulin (10(-7) m) significantly increased protein secretion in lacrimal gland acini whereas all growth factors tested significantly increased [Ca2+]i at 10(-7) m. TGF-alpha (10(-9) m), heregulin (10(-7) m), EGF (10(-7) m), and HB-EGF (10(-7) m) significantly increased the amount of phosphorylated MAPK in lacrimal gland acini. We conclude that all members of the EGF family of growth factors studied are synthesised in rat lacrimal gland, could activate all four ErbB receptors that are present in this tissue, and differentially activate lacrimal gland functions.