Immunohistochemical long-term evaluation of laminin expression in microvascular anastomoses of the carotid artery in the Wistar rat

Immunohistochemical study of NF-E2-related factor 2 (Nrf2) in an end-to-end anastomosis of the rat carotid artery

INTRODUCTION

The detailed process and underlying mechanism of stenosis following microvascular anastomoses remains unclear. NF-E2-related factor 2 (Nrf2), is a pleiotropic regulator of cell survival and plays a crucial role in modulating acute inflammatory response. An animal experiment was employed to obtain new information on the histomorphological changes and distribution of Nrf2 in anastomoses.

METHODS

An end-to-end anastomotic model in rat carotid arteries was carried out. The stoma was examined by H&E staining and immunostaining to evaluate histomorphological change as well as the intensity of anti-Nrf2 and а-SMA staining.

RESULTS

Compression, dehiscence and inflammatory cells infiltration were often seen following vessel anastomoses. Inflammatory cells infiltrate was reduced and the granulation tissue fibrosis and endothelium reforming become apparent with times. Marked tunica media hyperplasia consisting of a packed layer of neogenetic smooth muscle cell was present around the anastomosis. Nrf2 expression was upregulated after the operation and was mainly distributed in the neogenetic smooth muscle cells.

CONCLUSION

Stenosis following the micro-artery anastomoses may be mainly due to the progressive myointimal hyperplasia in the media of the arteries. Nrf2 was involved in the pro-inflammatory stress during the vascular morphogenesis/angiogenesis and can be a valuable tool for studying the process of wound healing.

Vascular invasion in breast cancer; an overview of recent prognostic developments and molecular pathophysiological mechanisms

Vascular invasion (VI) is an essential step in breast cancer metastasis and the main cause of morbidity and mortality from the disease. Detection of VI in the primary tumour is a marker of metastatic potential. The prognostic value of VI in breast cancer has been known for more than four decades, but its application in clinical practice is still fraught with difficulties due to the limited number of studies conducted on large numbers of well-characterized patients with long-term follow-up. Detection of VI in the primary tumour is currently assessed using sections stained with haematoxylin and eosin, which has some disadvantages. A number of vascular markers have been used to improve detection of VI; however, their sensitivity and specificity, as endothelial markers, vary considerably. In this review we describe the evolution of the prognostic importance of VI and the recent pathomolecular mechanisms that contribute to the ability of breast cancers to invade through vessels, in addition to the types, locations and methods of detection of vascular invasion.

Investigation of the effects of heparin and low molecular weight heparin on E-cadherin and laminin expression in rat pregnancy by immunohistochemistry

BACKGROUND

Heparin and low molecular weight heparin (LMWH) are used widely to improve the pregnancy outcome in women with thrombophilia, miscarriage, recurrent miscarriage and fetal death. This study was designed to investigate the effects of heparin and LMWHs, enoxaparin and tinzaparin, on E-cadherin and laminin expression in placental and decidual tissues in rat pregnancy.

METHODS

Wistar albino female rats (n = 48) were randomly assigned to four study groups (normal saline, heparin, enoxaparin and tinzaparin) in the preconceptional period. Tissue sections of placenta and decidua were immunohistochemically examined for the expression of E-cadherin and laminin.

RESULTS

E-cadherin placental staining score of heparin group was significantly lower and E-cadherin decidual staining score of heparin and enoxaparin groups were significantly lower than control group. There were no significant differences in placental and decidual laminin staining scores among the study groups.

CONCLUSIONS

Heparin and enoxaparin can reduce E-cadherin expression but not laminin expression in rat pregnancy. They might modulate trophoblast invasion. We suggest that this is the possible underlying mechanism involving in improvement of trophoblast invasion by the use of heparin and LMWH in patients with the history of miscarriage.