RESUMO
Previous studies indicate that the activity of hypothalamic POMC neurons can be regulated by glucose via intracellular mechanisms, but its regulation by lactate is poorly understood. In addition to its energetic role, lactate acts as a signaling molecule. In this study, we evaluated the function and location of the lactate receptor, hydroxycarboxylic acid receptor 1 (HCAR1). We used a conditional genetic approach to label POMC neurons and evaluated their sensitivity to lactate using patch-clamp recordings. L-Lactate and 3-chloro-5-hydroxybenzoic acid (3Cl-HBA), HCAR1 specific agonist depolarized POMC neurons and the increase in excitability was abolished by pertussis toxin (PTX), indicating the involvement of Gαi/o-protein-coupled receptors. In addition, the depolarization of a subset of POMC neurons was sensitive to α-cyano-4-hydroxycinnamate (4-CIN), a lactate transporter blocker, suggesting that the depolarization induced by L-lactate can also occur by direct intracellular action. Surprisingly, HCAR1 was not detected in POMC neurons, but instead localized in astrocytes. These results suggest a new lactate-mediated mechanism for astrocyte-neuron intercellular communication.
Assuntos
Ácido Láctico/metabolismo , Pró-Opiomelanocortina/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Astrócitos/metabolismo , Comunicação Celular/fisiologia , Feminino , Hipotálamo/metabolismo , Hipotálamo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transportadores de Ácidos Monocarboxílicos , Neurônios/metabolismo , Pró-Opiomelanocortina/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Se presentan 42 histeroscopias quirúrgicas, la mayoría corresponden a pólipos endometriales y miomas submucosos, causantes de sangramiento uterino anormal. Se enfatiza la eficacia del procedimiento y se discute la utilidad del uso del misoprostol para facilitar la dilatación cervical
Assuntos
Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Endometriose/cirurgia , Histeroscopia , Metrorragia/etiologia , Misoprostol/administração & dosagem , Doenças Uterinas/cirurgiaRESUMO
El embarazo cervical es una complicación obstétrica poco frecuente pero que representa un riesgo vital para las pacientes. Actualmente es posible efectual un diagnóstico precoz del embarazo cervical basado en el uso de la ultrasonografía transvaginal y en la medición de los niveles de ß-HCG. Su manejo terapéutico es controversial existiendo numerosas alternativas de tratamiento destinadas a disminuir la mortalidad y preservar la fertilidad de las pacientes. Nuestro objetivo es presentar un caso clínico de un embarazo cervical, estudiado y manejado en nuestro servicio, y discutir los elementos diagnósticos y terapéuticos actuales