RESUMEN
Tenascin-C (TN-C), an extracellular matrix glycoprotein, is known to be expressed in uterine stroma in the peri-implantation period. Examination of the spatiotemporal pattern during early pregnancy using immunohistochemistry and in situ hybridization revealed TN-C expression in the stroma beneath the luminal epithelia of the murine endometrium on Days 0 and 1 of pregnancy, subsequent disappearance, and reappearance on Day 4. After decidualization, tissue around the deciduoma was positive. In situ hybridization demonstrated TN-C production by the stromal cells adjacent to the epithelia. To investigate the regulation of TN-C expression in vitro, murine uterine stromal and epithelial cells were isolated and cultured. Addition of interleukin-1 alpha (IL-1 alpha) and prostaglandin E(2) (PGE(2)) and F(2 alpha) (PGF(2 alpha)) induced TN-C expression in the stromal cells at both protein and mRNA levels, while the sex steroid hormones, progesterone and ss-estradiol, exerted little effect. Immunohistochemistry using anti-IL-1 alpha antibody showed epithelial cells to be positive on Days 2-4 of pregnancy, and addition of progesterone but not ss-estradiol enhanced IL-1 alpha expression in epithelial cells in vitro. In a culture insert system, TN-C expression by stromal cells cocultured with epithelial cells was induced by addition of progesterone alone that was blocked by additions of anti-IL-1 alpha antibody. Collectively, these findings indicate that TN-C expression in the preimplantation period is under the control of progesterone, but not directly, possibly by the paracrine and autocrine intervention of IL-1 alpha secreted by epithelial cells and PGE(2) and PGF(2 alpha) secreted by stromal cells.
Asunto(s)
Dinoprost/fisiología , Dinoprostona/fisiología , Interleucina-1/fisiología , Preñez/metabolismo , Células del Estroma/metabolismo , Tenascina/biosíntesis , Útero/metabolismo , Animales , Células Cultivadas , Técnicas de Cocultivo , Cartilla de ADN , Digoxigenina , Dinoprost/biosíntesis , Dinoprost/genética , Dinoprostona/biosíntesis , Dinoprostona/genética , Endometrio/citología , Endometrio/metabolismo , Células Epiteliales/metabolismo , Femenino , Inmunohistoquímica , Hibridación in Situ , Interleucina-1/biosíntesis , Interleucina-1/genética , Ratones , Ratones Endogámicos C3H , Embarazo , Preñez/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tenascina/genética , Útero/citologíaRESUMEN
A 77-year-old man with malignant lymphoma presented with dizziness and exertional dyspnea. Physical examination revealed marked bradycardia (36 beats/min). Twelve-lead electrocardiography showed complete atrioventricular block with narrow QRS escape beats. Gallium scintigraphy demonstrated significant abnormal uptake in the heart. Transesophageal echocardiography showed a thick interatrial septum with increased echogenecity. He underwent chemotherapy under external temporary pacing with a suspected diagnosis of complete atrioventricular block secondary to cardiac invasion of malignant lymphoma. Atrioventricular conduction progressively improved and the complete atrioventricular block disappeared. He is currently well and has required no cardiac pacing for 6 months. We conclude that complete atrioventricular block may be reversible in some patients with malignant lymphoma, even in the elderly.
