Reference no: EM132869013 , Length: word count:1500
BL2014 Tissues to Organisms and Physiology & Pharmacology - University of Central Lancashire
Assignment: The effect of metabolites on myosin ATPase (muscle contraction) as a possible mechanism of peripheral muscle fatigue.
Background
It is well established that contraction of striated muscle is due to the cyclic interaction of myosin in the thick filaments of the sarcomere and actin in the thin filaments. Myosin heads attach to actin and the resultant structural change leads to filament sliding and the subsequent detachment of the heads. This is thought to occur asynchronously many times during contraction. Adenosine triphosphate (ATP) provides the immediate source of energy for muscle contraction. Hydrolysis of the bonds between the phosphate residues of ATP are associated with the release of a large amount of energy. In muscle the hydrolysis of ATP to adenosine diphosphate (ADP) is catalysed by the contractile protein myosin, thus adenosine triphosphatase (ATPase) activity is found in the heads of the myosin molecules where they are in contact with actin.
In these studies use is made of glycerinated fibres of rabbit psoas muscle, which provides an excellent opportunity for practical studies of muscle ultrastructure and mechanism of contraction. A Glycerinated muscle fibre is obtained by taking muscle fibres from a freshly killed animal and immersing in equal volumes of water and glycerol at 00C and subsequently storing at -200C. This treatment leaves the contractile structure intact whilst perforating the cell membrane (sarcolemma) and removing other factors such as ATP and destroying the ATP-restoring systems. By the use of appropriate chemicals, the fibre can be made to relax, to contract or be made extensible.
You should structure your lab report using the following subheadings:
Introduction, aims and hypotheses.
This should provide a brief review of literature including a discussion of our current knowledge of the mechanisms of peripheral muscle fatigue specifically at the myosin head and involving myosin ATPase. The introduction should finish with clearly defined aims of the study and any hypotheses you may have had before collecting data. You must cite the original journal articles.
Methods.
This should be written in the past tense and your own words referring to the laboratory handout to keep the word count down. Avoid using bulleted lists (look at the Journal of Physiology as a guide for formatting methods sections in research papers).
It is not necessary to include a list of equipment but instead to give a clear indication of the protocol used, identifying the control and the experimental conditions. Make reference to the statistical analysis.
Results.
Results should be presented using appropriate graphs. For each variable plotted, i.e. pH and [Pi], make sure you include a brief commentary for the results and any statistical data. Present the means and standard deviations from the class data. The figures including the legend are excluded from the word count.
Describe the statistical tests used on the data. Use an appendix for the SPSS output table This is excluded from the word count.
Attachment:- Tissues to Organisms and Physiology.rar