RESUMO
Introducción: La dermatitis atópica (DA) severa suele tener un componente psiquiátrico que puede influir en el desencadenamiento y exacerbación de los síntomas cutáneos. La neuroimagen funcional podría objetivar disfunciones neuronales existentes en estos pacientes.Objetivo: Investigar la presencia de trastornos de la perfusión cerebral en pacientes con DA severa y describir sus características mediante SPECT. Materiales y métodos: 11 pacientes adultos con DA severa fueron estudiados por evaluación psiquiátrica clínica y SPECT cerebral con 99mTc-ECD. Resultados: 90.3 por ciento de los pacientes presentaron un trastorno de ansiedad generalizada, 63.6 por ciento un trastorno obsesivo compulsivo y 63.6 por ciento depresión. Todos los pacientes presentaron trastornos de perfusión, que predominaron en la corteza prefrontal. Se evidenciaron alteraciones concordantes con los patrones descritos en pacientes que asocian síntomas depresivos y ansiosos. Conclusiones: Demostramos la presencia frecuente de alteraciones de la perfusión cerebral en la DA severa con componente psiquiátrico y describimos sus características mediante un método de neuroimagen.
Assuntos
Masculino , Adolescente , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão de Fóton Único , Circulação Cerebrovascular/fisiologia , Compostos de Organotecnécio , Dermatite Atópica/complicações , Telencéfalo , Transtornos Mentais , Transtornos Mentais/etiologia , Depressão/etiologia , Fatores Desencadeantes , Compostos Radiofarmacêuticos , Telencéfalo/irrigação sanguínea , Transtorno Obsessivo-Compulsivo/etiologia , Transtornos de Ansiedade/etiologiaRESUMO
Situations of stress are capable of inducing depression and oxidative stress in the brain. Previous reports have shown that angiotensin II (Ang II) induces the production of superoxide anion (O(2)(-)), and impairment of endothelial function in cerebral microvessels in vivo. Substances that reduce angiotensin functions may be important in the treatment of depression. These data suggest a role for both Ang II and O(2)(-) in depression; thus, the aim of this study was to determine the effect of forced swimming test (FST), a model of stress/depression, on the cellular expression of Ang II and O(2)(-) in the central nervous system. To induce stress/depression, rats were subjected to FST daily (30 min) for 15 days. Unstressed animals were used as controls. Motor activity was automatically analyzed daily before swimming. Cerebrum and cerebellum frozen sections were studied for O(2)(-) by a histochemical method and for Ang II producing cells by a polyclonal antibody. In the FST group, struggle time, total horizontal activity, ambulatory movements, and vertical movements, were significantly decreased when the data from the 1st and 15th day were compared. Food intake and body weight gain also decreased when unstressed and FST rats were compared at the 15th day. Increased number of cerebrum and cerebellum O(2)(-), and Ang II positive cells, were observed in FST rats. Significant correlation was found between O(2)(-) positive cells and Ang II positive cell in the cerebrum. These results suggest that stress/depression situations could be involved in the increase of Ang II and oxidative stress in the central nervous system, with possible implications in the depressive condition.
Assuntos
Angiotensina II/metabolismo , Encéfalo/metabolismo , Transtorno Depressivo/metabolismo , Estresse Oxidativo/fisiologia , Estresse Psicológico/metabolismo , Superóxidos/metabolismo , Animais , Peso Corporal/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Contagem de Células , Cerebelo/irrigação sanguínea , Cerebelo/metabolismo , Cerebelo/fisiopatologia , Artérias Cerebrais/metabolismo , Artérias Cerebrais/fisiopatologia , Transtorno Depressivo/complicações , Transtorno Depressivo/fisiopatologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Imuno-Histoquímica , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/complicações , Estresse Psicológico/fisiopatologia , Natação/psicologia , Telencéfalo/irrigação sanguínea , Telencéfalo/metabolismo , Telencéfalo/fisiopatologia , Regulação para Cima/fisiologiaRESUMO
The origin of the blood supply to the brain and arteries of the ventral surface of the brain was studied in 31 adult chinchillas (Chinchilla lanigera). The arterial system was filled with latex 603 via the brachioencephalic trunk and the left subclavian artery, both of which arose from the aortic arch in most cases. The right and left internal carotid arteries (100% and 93.3%, respectively) did not contribute to the brain supply. The vertebral arteries were present in all cases and formed the basilar artery (96.7%) that gave off the ventral spinal artery caudally in all cases. The caudal cerebellar artery was single (80%) or double (20%) on the right, and single (70%) or double (30%) on the left. The rostral cerebellar artery was present as a caudal vessel on the right (73.3%) and on the left (70%), and as a rostral vessel in all cases. The rostral tectal artery was single in all cases. The caudal cerebral artery was single (53.3%), double (36.7%) or triple (10%) on the right, and single (46.7%), double (46.7%) or triple (6.7%) on the left. The hypophyseal artery was present in all cases. The internal ophthalmic artery was present only on the right (26.7%), or only on the left (23.3%). The middle cerebral artery was single in all cases on both sides. The rostral cerebral artery was present as a well-developed (96.7%) or vestigial (3.3%) vessel in both antimeres, gave off lateral arteries to the olfactory bulb and the median rostral inter-hemispheric artery, and ended as the internal ethmoidal artery. The cerebral arterial circle was open (70%) or closed (30%) rostrally, and closed caudally in all cases. The brain was supplied almost exclusively by the vertebral-basilar system.
Assuntos
Animais , Masculino , Feminino , Artérias Cerebrais/fisiologia , Artérias Cerebrais/química , Sistema Nervoso Central/fisiologia , Telencéfalo/irrigação sanguínea , ChinchilaRESUMO
The pregnant llama (Lama glama) has walked for millions of years through the thin oxygen trail of the Andean altiplano. We hypothesize that a pool of genes has been selected in the llama that express efficient mechanisms to withstand this low-oxygen milieu. The llama fetus responds to acute hypoxia with an intense peripheral vasoconstriction that is not affected by bilateral section of the carotid sinus nerves. Moreover, the increase in fetal plasma concentrations of vasoconstrictor hormones, such as catecholamines, neuropeptide Y, and vasopressin, is much greater in the llama than in the sheep fetus. Furthermore, treatment of fetal llamas with an alpha-adrenergic antagonist abolished the peripheral vasoconstriction and resulted in fetal cardiovascular collapse and death during acute hypoxia, suggesting an indispensable upregulation of alpha-adrenergic mechanisms in this high altitude species. Local endothelial factors such as nitric oxide (NO) also play a key role in the regulation of fetal adrenal blood flow and in the adrenal secretion of catecholamines and cortisol. Interestingly, in contrast to the human or sheep fetus, the llama fetus showed a small increase in brain blood flow during acute hypoxia, with no increase in oxygen extraction across the brain, and thereby a decrease in brain oxygen consumption. These results suggest that the llama fetus responds to acute hypoxia with hypometabolism. How this reduction in metabolism is produced and how the cells are preserved during this condition remain to be elucidated.