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An abstract of the article "Bioinformatic and experimental validation of 3' exon alternative splicing of Myosin Phosphatase Targeting (MYPT) subunits in human muscles" by J. Lartey, K. North, J. Taggart, S. C. Robson and M. Taggart is presented.

An abstract of the article "Analysis Of Calmodulin Dependent Kinase II CaMKII)-delta and -gamma subunit expression between three different human smooth muscle tissues" by J. Lartey, J. Taggart, S. C. Robson and M. J. Taggart is presented.

An abstract of the article "Evaluation of small molecule inhibitors of nuclear factor kappa B (NFkB) in abrogating cytokine-stimulated signalling in isolated human myometrial cells" by L.R. Gurney, J. Taggart, S. Robson and M. Taggarr is presented.

Myosin phosphatase is a trimeric protein that regulates vascular tone by inducing dephosphorylation of smooth muscle regulatory myosin light chains. The 110-130 kDa myosin phosphatase targeting subunit (MPYT) is essential for this process. Nitric oxide- mediated arterial relaxation has been suggested to occur partly via PKG interactions with a leucine zipper (LZ) region of MYPT1 that is generated by alternative exon splicing of the 3' end of the gene [1]. The relative expression of MYPT1 LZ+ to LZ- isovariants may thus influence arterial sensitivity to endothelial-mediated vasodilators and/or NO donors. Interestingly, the sensitivity of isolated human myometrial arteries to endothelial-mediated vasodilators is greater than that of placental arteries from pregnant women (2). In addition, non-vascular uterine smooth muscle shows variable responsiveness to NO donors. We propose that tissue-specific differences in human MYPT1LZ+ to LZ- isovariant expression, not previously assessed in human tissues, may offer an explanation for these findings. Human tissue samples were obtained, following written informed consent, from normal pregnant women undergoing elective Caesarean section at term. Myometrium, myometrial arteries (MA) and placental arteries (PA) were microdis-sected free of all surrounding tissue. The human MYPT1LZ+ sequence (NM_002480.1) was aligned with chicken (NM_205123) and mouse (NM_027892) MYPT1 LZ-sequences to detect a shift in the reading frame that generates the putative human MYPT1 LZ- sequence. RNA was isolated (Qiagen RNeasy fibrous kit) and reverse transcribed (Stratagene AffinityScript cDNA synthesis Kit) from the human tissues and qPCR, with isovariant-specific primers and PerfectProbe amplification (Primer Design, UK), used to measure MYPT1LZ+ and MYPT1LZ- isovariant expression. Human smooth muscle RNA (Clonetech, USA) was used as an internal calibrator. MYPT1LZ+ expression was less in the myometrium (fold-change relative to calibrator RNA of 0.33+0.04) than MA (1.33+0.12) and PA (2.07+0.17; p<0.01, n=10, mean+SEM, ANOVA). A similar pattern was seen for MYPT1 LZ- expression wherein changes relative to calibrator were 0.06+0.17 (myometrium), 0.45+0.05 (MA) and 0.65+0.07 (PA). This reveals differences in MYPT1LZ+ and MYPT1LZ- expression between human myometrium, MA and PA. Of note, the ratio of MYPT1LZ+to LZ-expression in MA was not greater than in PA. As the former is more sensitive to endothelial-dependent relaxant agonists, this suggests that a correlation between MYPT1LZ+ expression and physiological sensitivity to PKG and/or NO stimulation in these human tissues may be an oversimplification. Further research is required, however, to determine such a relationship in relevant clinical conditions of heightened smooth muscle tone. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVDs) account for almost 191,000 deaths per year in the UK -- one in three of all deaths [1]. Age-related functional and structural changes in the resistance vasculature, with consequent alterations in arterial tone, contribute to the overall risk of CVD. There appears to be a marked difference in the prevalence of CVD in men and women, with the risk being smaller in women than men aged 30-50. After the menopause, however, the incidence of CVD increases in women and approaches the incidence rate of men [2] indicating a potential beneficial effect of oestrogen although this has resisted absolute confirmation. Therefore, a clearer understanding of vascular functional changes with ageing, and the influence of oestrogens therein, would be informative for assessing effective cardio-protective treatment options in older women. The aims of this study were to investigate the effects of relaxing agents, including 17-ß oestradiol (17-ß) and oestrogen receptor (ER)-specific agonists, on small arteries from young (3 month) and aged (24 month) female C57BL mice. Uterine, mesenteric and tail arteries (<250µm) were dissected and mounted on a wire myograph for isometric force measurement. Endothelium-dependent relaxations were assessed in each by the addition of increasing concentrations of acetylcholine (Ach) (0.1nm - 10µM) to maximally constricted arteries. In addition, arteries were maximally pre-constricted with the thromboxane agonist U46619 (1µM) then exposed to increasing concentrations of one of two ER specific agonists, PPT (ER-α) and DPN (ER-ß) or 17-ß. Changes in tension were measured and responses between groups were compared using 2-way ANOVA (p<0.05 was significant). Ach-induced relaxations were significantly reduced in all artery types (maximal relaxations (%): UA Young: 57.2±4.0, UA Aged: 43.0±2.6, TA Young: 61.8±5.1, TA Aged: 43.6±2.2, MA Young: 34.1±1.9, MA Aged: 14.6±2.0). In arteries of young and aged mice, concentration-dependent relaxations of all three artery types were induced by 17-ß and PPT. For example, maximal relaxations (%) for UA (n=7), TA (n=9) and MA (n=9), to 17-ß from young mice were 54.4±3.5, 52.0±5.4, and 63.3±5.1 and from old mice were 58.8±4.9, 36.6±5.1, and 72.0±7.3. However, in contrast, DPN significantly relaxed arteries of young mice (maximal relaxations for UA, TA and MA, respectively: 38.1±2.5, 21.6±1.5, and 42.2±4.6) but failed to do so in UA or TA from old mice. In summary, age-dependent alterations in endothelial-dependent function are shared across several arteries from distinct vascular beds. In contrast, tissue-specific effects of ageing are evident in arterial vasodilation by the putative ERß-specific agonist DPN. The data alerts one to the need to consider tissue-specific responses when exploring age-related changes in vascular function. [ABSTRACT FROM AUTHOR]