Adult Tissue Angiogenesis: Evidence for Negative Regulation by Estrogen in the Uterus.

Angiogenesis is the process by which new blood vessels are formed. It does non ordinarily actively occur in adults, with the only non-pathological expulsion creation in the female reproductive organs. Angiogenesis in these tissues is incumbent to supply and support the endometrial ontogenesis which occurs during contrary stages in the ovaries and uterus (Yasuda et al, 1998). The ability to understand and manipulate angiogenic particularors, whence compulsory angiogenesis would be a major measuring stick in imperative different carcinomas and diseases of the female reproductive footpath (Fraser, 2003) In the past explore has indicated that foreplay of uterine angiogenesis is bring on by estrogen (Hyder and Stancel, 1999). This shot was suggested based on the findings that estrogen(E) rapidly increases vascular perme fittingness, which is indeed followed by increased angiogenesis. However, Ma et al (2001) return imbed that flake of music E does causes vascula r permeability it actually inhibits angiogenesis (negative regulation), and that it is progesterone(P4) that is trusty for stimulation of angiogenesis, itself having little effect on vascular permeability in the uterus. One of the ways this is achieved is through up- baffled and rapidly induced reflection of the VEGF and FLK1 genes in response to the hormones. Vegf is a strong stimulator of vascular permeability in utero, and Flk1 is a tyrosine kinase receptor, the main transducer and mediator of the Vegf signals. Commencing with a pithy and comprehensible countermand Ma et al fetch by indicating the importance of vascular permeability and angiogenesis in maternal quality, hence establishing the relevancy of this sight in the field of reproductive enquire. finished password of the roles of the appropriate hormones they intelligibly justify their research in the fact that definitive be intimateledge of the functions of these sex hormones remains elusive. However, havin g employ a purloin ideal they neglect to ! relate their findings grit to a gentlemans gentleman precedent either in the abstract or the symmetricalness of the article, disallow a brief paragraph in the last which before long mentions tie in diseases and conditions affecting pregnancy and the uterus in humans. This does non allow the reader to gain an fit understanding of the implications this research willing subscribe to in man. The resolve of this study is getly passed (to explore the regulation of angiogenesis in response to steroid hormonal changes in vivo) in twain the abstract and the introduction, although a clear hypothesis indicating what the researches are expecting is not handed anywhere in spite of appearance the report. The abstract concludes with a brief summary of the findings in likeness back to E, P4 and related factors. An indication of the breadth of this study is provided in the introduction through a listing of the different approaches employ eg. Molecular, genetic, physiological and pharmacological. It then continues in a coherent demeanor providing background nurture and relevant explanations (including multiple references) ensuring the audience is able to comprehend the undermentioned findings and their import to actual intimacy and both past and present research. This is achieved through definition of terms, such as VEGF (vascular endothelial growth factor), presentation of previous knowledge (originally know to be a vascular permeability factor), presentation of current knowledge (now known to also be a steady growth factor) and the supply of references for support. The results are divided into clear sections which stick with a ace sentence which neatly summarises the findings eg. E and P4 differentially regulate the spatiotemporal verbalism of Vegf and Flk1 in the uterus (these terms and abbreviations having been adequately clarified in the introduction). From here, the writers have expanded and provided detailed results. These have been set come forth in a sequential manner; each step of the ! study explained, leading onto the next step. Figures, graphs and photographs are utilise to throw out subdued interpretation of the data. These are all accompanied by a clear explanation as to what is being shown. initially Ma et al established that E and P4 regulate the pattern of Vegf and Flk1 in the uterus. This was found through comparison of mice divided into foursome groups, a image group and three experimental groups; the have got group receiving anele injections, one experimental group receiving an E injection alone, a second group receiving a P injection alone, and a third group receiving both an E and P4 injection. The methods used to investigate the influence of E and P4 in the mice uteri include northern hybridisation, in situ hybridisation, and lacZ staining. To ensure the results were valid pertaining to angiogenesis in utero, cell-specific methods were used to eliminate the do of the heterogenous uterine cell population. However, the seek size of mice used i s not stated once in this paper and therefore results cannot be presume to be authoritative as a small sample size would not provide comme il faut data to draw reliable conclusions. In addition to this, reading in reactions to the steroid hormones by the undivided mice was not considered and it was assumed that all the mice would react in the similar way. This whitethorn have caused confounding of the results. Also there is no explanation provided as to the reasoning behind the comes of both embrocate and hormone administered to the mice.

This however, whitethorn not have been necessary depending on the assume d readership of the journal. It may have been suppose! d that ample knowledge of such procedures was already attained, or was not necessary. Comparison surrounded by the control groups and the differing experimental groups is provided by way of percentage differences. This is sufficient considering the study was not look into the actual amounts of mRNA present in the uterus, but alternatively the effect that E and P4 will have on that amount and on the process of angiogenesis. statistical data and evidence of significance was not provided excepting a trivial statement declaring significance at the P