Aging-related growth hormone - Essay Example

The process of aging is related to the decreased secretions of the growth hormone. As the age increases, the deposition of the fat in the adipose tissues and the fatigue has been related to the diminishing effectiveness of the growth hormone with the increasing age.As compared to the previous study, which has,some inaccurate findings related to the growth hormones relation to the process of aging,this study's importance lies in the fact that the correct hypothesis should be established based on the results using accurate procedures.

The earlier hypothesis established that the lower growth hormone release in elderly persons is due to the decreased hypothalamic growth hormone-releasing hormone release. The study was performed again to produce an accurate hypothesis related to age and growth hormone release.Having four groups, which included five young men, 8 young women, 10 elderly men and 11 elderly women, concluded the study methodology. Healthy, physically active subjects, with similar BMIs (body mass indexes) having healthier life styles were selected.

The heparinized saline-filled cannula was inserted in a forearm vein of all the subjects.Blood samples were collected after every 10 minutes for 24 hours. Eating in the middle of the meals was not allowed. The subject was required to sleep or rest in bed for the period of 6.30 to 7 hours. Sleeping was not allowed between 7:00am to 11:00pm. Plasma growth hormone levels were measured in duplicate by a chemiluminometric assay. Plasma insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), testosterone, and estradiol were measured from a sample created by collecting equal amounts of plasma samples that were obtained after every 4 to 6 hours from each subject.

Total IGF-I was measured after acid-ethanol extraction by an immunoradiometric assay. The statistical analysis: The variables in the study The growth hormone release variables were analyzed by Cluster analysis utilizing a power function variance model, t scores of 2, and a cluster size of 2x2. Maximum and minimum growth hormone (g/l) was defined as the highest and lowest growth hormone concentrations measured during the 24-hour period for each subject. Growth hormone (g/l) was determined as the average of the lowest 5% (7 points) of the growth hormone values measured during the 24-hour period.

Integrated growth hormone concentration (gxmin/l) was defined as the area under the growth hormone versus time curve for each individual time period using trapezoidal calculations. The variable of the time factor To compare whether there was a difference in the timing of the peak (maximum) growth hormone pulse, subjects were divided into those having the maximum pulse during the "lights off" or the sleeping period or during the "lights on" period. Fisher's exact test was then used to determine if there was a difference between the young and elderly subjects.

Due to multiple comparisons, Bonferroni correction was applied, and a difference was considered significant at the p