Neuropeptide Y Y(1) receptor regulates protein turnover and constitutive gene expression in hypertrophying cardiomyocytes.

Increased levels of neuropeptide Y correlate with severity of left ventricular hypertrophy in vivo. At cardiomyocyte level, hypertrophy is characterised by increased mass and altered phenotype. The aims were to determine the contributions of increased synthesis and reduced degradation of protein to neuropeptide Y-mediated increase in mass, assess effects on gene expression, and characterise neuropeptide Y Y receptor subtype involvement. Neuropeptide Y (10 nM) increased protein mass of adult rat ventricular cardiomyocytes maintained in culture (24 h) (16%>basal) and de novo protein synthesis (incorporation of [14C]phenylalanine) (18%>basal). Neuropeptide Y (100 nM) prevented degradation of existing protein at 8 h. Actinomycin D (5 µM) attenuated increases in protein mass to neuropeptide Y (=1 nM) but not to neuropeptide Y (10 nM). [Leu31, Pro34]neuropeptide Y (10 nM), an agonist at neuropeptide Y Y1 receptors, increased protein mass (25%>basal) but did not stimulate protein synthesis. Neuropeptide Y-(3–36) (10 nM), an agonist at neuropeptide Y Y2 receptors, increased protein mass (29%>basal) and increased protein synthesis (13%>basal), respectively. Actinomycin D (5 µM) abolished the increase in protein mass elicited by neuropeptide Y-(3–36) but not that by [Leu31, Pro34]neuropeptide Y. BIBP3226 [(R)-N2-(diphenylacetyl)-N-(4-hydroxyphenylmethyl)-d-arginine amide] (1 µM), a neuropeptide Y Y1 receptor subtype-selective antagonist, and T4 [neuropeptide Y-(33–36)]4, a neuropeptide Y Y2 receptor subtype-selective antagonist, attenuated the increase in protein mass to 100 nM neuropeptide Y by 68% and 59%, respectively. Neuropeptide Y increased expression of the constitutive gene, myosin light chain-2 (MLC-2), maximally at 12 h (4.7-fold>basal) but did not induce (t=36 h) expression of foetal genes (atrial natriuretic peptide (ANP), skeletal-a-actin and myosin heavy chain-ß). This increase was attenuated by 86% and 51%, respectively, by BIBP3226 (1 µM) and T4 [neuropeptide Y-(33–36)]4 (100 nM). [Leu31, Pro34]neuropeptide Y (100 nM) (2.4-fold>basal) and peptide YY-(3–36) (100 nM) (2.3 fold>basal) increased expression of MLC-2 mRNA at 12 h. In conclusion, initiation of cardiomyocyte hypertrophy by neuropeptide Y requires activation of both neuropeptide Y Y1 and neuropeptide Y Y2 receptors and is associated with enhanced synthesis and attenuated degradation of protein together with increased expression of constitutive genes but not reinduction of foetal genes.

Organisational Self-Evaluation and Teacher Education for Community Relations in a Transforming Society?

During 2004, the School of Education at the University of Ulster embarked on an innovative three-year project designed to embed community relations objectives within initial teacher education. With the advent of more peaceful times in Northern Ireland, this was a precipitous time for initial teacher educators to review the preparation given to beginner teachers for teaching in an increasingly pluralist society emerging from conflict. The present paper reports on one very specific and time-limited element of the broader project. That is, development work designed to investigate the possibilities of using processes of self-review and evaluation as a lever for improvements in initial teacher education for community relations. Following a brief contextualisation, the background to, and the development of, a set of materials designed to support rigorous and systematic self-review of all aspects of provision in a university-based initial teacher education department is described. The Community Relations Index for Initial Teacher Education (Cr-ITE) was envisaged as being of use to initial teacher education establishments in order to help teacher educators take responsibility for rigorous learning from their practice, whilst placing inclusive values at the centre of organisational development. The final section includes further critical reflection on the role of organisational self-review in transforming teacher education for inclusion in a society emerging from longstanding communal conflict.

Primary science teacher confidence revisited: ten years on

Background

Conceptions of Teacher Identity: Creating Self-Boxes as Arts-Based Self-Study

This paper presents a palimpsest of ways in which self-study draws upon arts-based methods not just as processes towards teacher development, but also as means to problematize and inquire into conceptualizations of the self. It focuses on the creation of individual self-boxes that mediate teachers’ dynamic narratives of identity. Concepts of the unitary self, the decentred self and the relationship between inner and outer experience are challenged and illustrated through two interlapping stories made manifest through the creation of self-boxes. From time immemorial man has known that he is the subject most deserving of his own study, but he has also fought shy of treating this subject as a whole, that is, in accordance with its total character. (Buber, 1947, p. 140)