Search Results

You are looking at 1 - 4 of 4 items for

  • Author or Editor: Jesús Vaquero x
  • By Author: Zurita, Mercedes x
Clear All Modify Search
Restricted access

Mercedes Zurita, Jesús Vaquero and Isabel Zurita

Object. A glycoprotein, CD95 (Fas/APO1) is widely considered to be implicated in the development of apoptosis in a number of tissues. Based on the hypothesis that apoptosis is related to cell death after spinal cord injury (SCI), the authors studied the presence and distribution of CD95 (Fas/APO1)-positive cells in injured spinal cord tissue for the purpose of determining the significance of this protein during the early phases of SCI.

Methods. The presence and distribution of cells showing positive immunostaining for CD95 (Fas/APO1) were studied 1, 4, 8, 24, 48, and 72 hours and 1, 2, and 4 weeks after induction of experimental SCI in rats. Studies were conducted using a monoclonal antibody to the CD95 (Fas/APO1) protein. Positivity for CD95 (Fas/APO1) was observed in apoptotic cells, mainly in the gray matter, 1 hour after trauma, and the number of immunostained cells increased for the first 8 hours, at which time the protein was expressed in both gray and white matter. From 24 to 72 hours postinjury, the number of immunostained cells decreased in the gray matter, but increased in the white matter. From then on, there were fewer CD95 (Fas/APO1)-positive cells, but some cells in the white matter still exhibited positive immunostaining 1 and 2 weeks after injury. At 4 weeks, there remained no CD95 (Fas/APO1)-positive cells in injured spinal cord.

Conclusions. These findings indicate that CD95 (Fas/APO1) is expressed after SCI, suggesting a role for this protein in the development of apoptosis after trauma and the possibility of a new therapeutic approach to SCI based on blocking the CD95 (Fas/APO1) system.

Restricted access

Mercedes Zurita, Jesús Vaquero, Santiago Oya and Carmen Morales

Object. The purpose of this study was to analyze the expression of F7–26 (Apostain) in injured spinal cord tissue, and the modifying effects of dexamethasone administration.

Methods. A total of 56 adult female Wistar rats were subjected to traumatic spinal cord injury (SCI) to induce complete paraplegia. These rats were divided into two groups according to whether they received dexamethasone (doses of 1 mg/kg daily) post-SCI. Injured spinal cord tissue was studied by means of conventional histological techniques, and Apostain expression was determined by immunohistochemical analysis at 1, 4, 8, 24, and 72 hours, and at 1 and 2 weeks after SCI in all the animals. Apostain-positive cells, mainly neurons and glial cells, were detected 1 hour after injury, peaking at 8 hours, after which the number decreased. One week after injury, apoptosis was limited to a few glial cells, mainly oligodendrocytes, and 2 weeks after injury there was no evidence of Apostain-positive cells. In the group of paraplegic rats receiving post-SCI intraperitoneal dexamethasone, there was a significant decrease in the number of Apostain-positive cells.

Conclusions. Analysis of the results indicated that apoptosis plays a role in the early period after SCI and that administration of dexamethasone decreases apoptosis-related cell death in the injured spinal cord tissue.

Restricted access

Jesús Vaquero, Mercedes Zurita, Santiago de Oya and Santiago Coca

Object. Predicated on the hypothesis that this cytokine can contribute to the development of vascular hyperpermeability, leading to tissue edema after trauma, the purpose of this study was to determine the presence in tissue of vascular endothelial growth/permeability factor (VEG/PF) after experimental spinal cord injury.

Methods. The presence of VEG/PF was studied at 8 hours and 2, 8, and 14 days after a traumatic injury in adult Wistar rats. Studies were conducted in which a monoclonal antibody to the VEG/PF was used. Strong VEG/PF immunoreactivity was detected in the walls of pial and intramedullary vessels and in reactive astrocytes 8 hours posttrauma and was unchanged on Days 2 and 8. By Day 14, immunoreactivity decreased, and most of the arterioles from the pia and gray matter showed no mural VEG/PF.

Conclusions. The authors' present findings suggest a role for this cytokine in the development of tissue edema after spinal cord trauma and point to the possible usefulness of a therapeutic approach to spinal cord injury based on blocking the cell expression of VEG/PF or its physiological effects.

Restricted access

Jesús Vaquero, Mercedes Zurita, Santiago de Oya, Santiago Coca, Carmen Morales and Clara Salas

Object. The expression of vascular endothelial growth/permeability factor (VEG/PF) has recently been correlated with the presence of tumor-associated cysts in some intracranial tumors. The purpose of this study was to evaluate a possible relationship between the presence of VEG/PF and the formation of cysts in craniopharyngiomas.

Methods. The expression of VEG/PF was studied in histological specimens from a series of 12 craniopharyngiomas. In this series, the tumors were classified as presenting a mainly solid pattern with small macroscopic cysts (four patients) or a mainly cystic pattern (eight patients). The mainly solid tumors containing small macroscopic cysts showed little or no VEG/PF positivity, which was mainly present in tumor cells surrounding cysts. Nevertheless, mainly cystic craniopharyngiomas showed a moderate or high degree of VEG/PF positivity in tumor cells.

Conclusions. These findings indicate that the predominance of a cystic or solid macroscopic appearance of craniopharyngiomas may be influenced by the degree of VEG/PF expression within the tumor cells.