How Commonly Used Psychoactive Drugs Affect The Hypothalamo-pituitary-adrenal Axis
Funder
National Health and Medical Research Council
Funding Amount
$411,448.00
Summary
The body makes a number of responses when it is subjected to stress, and these include the secretion of hormones from the adrenal gland, including cortisol. It is not surprising that cortisol has effects upon the way the brain operates, nor is it surprising that diseases that are associated with stress (e.g. depression, alcoholism and other psychiatric complaints) create abnormal cortisol secretion. The drugs that are known to be successful in treating conditions such as depression and anxiety h ....The body makes a number of responses when it is subjected to stress, and these include the secretion of hormones from the adrenal gland, including cortisol. It is not surprising that cortisol has effects upon the way the brain operates, nor is it surprising that diseases that are associated with stress (e.g. depression, alcoholism and other psychiatric complaints) create abnormal cortisol secretion. The drugs that are known to be successful in treating conditions such as depression and anxiety have been shown to affect the secretion of cortisol, but, somewhat paradoxically, we do not precisely know how they operate. The aim of this research is to examine how drugs that are commonly used for the treatment of a number of psychiatric conditions (e.g. Prozac, Tofranil, Xanax, morphine and naltrexone) affect the secretion of hormones from the brain that ulitmately regulate the secretion of cortisol. We propose that the effects of these drugs is related to how they operate, and for how long they have been given. The findings generated by this research may help us determine new ways of diagnosing and treating a range of conditions.Read moreRead less
The Role Of Ghrelin And Growth Hormone Releasing Hormone In The Autocrine Regulation Of Prostate Cancer Cell Growth
Funder
National Health and Medical Research Council
Funding Amount
$240,990.00
Summary
Insulin-like growth factor-I (IGF-I) is an important growth factor with a major role in the growth and development of many normal and tumour cells. Its production is controlled by growth hormone (GH), released from the pituitary gland at the base of the brain. GH releasing hormone (GHRH), a hormone released from higher centres in the brain, regulates the production of GH itself and now it is recognised that a second pathway, the ghrelin-GH secretagogue receptor (GHS-R) axis is also important in ....Insulin-like growth factor-I (IGF-I) is an important growth factor with a major role in the growth and development of many normal and tumour cells. Its production is controlled by growth hormone (GH), released from the pituitary gland at the base of the brain. GH releasing hormone (GHRH), a hormone released from higher centres in the brain, regulates the production of GH itself and now it is recognised that a second pathway, the ghrelin-GH secretagogue receptor (GHS-R) axis is also important in regulating GH release. There is growing evidence that the GHRH-GH-IGF axis has a significant role in prostate cancer, but little is known about how this happens. We also have evidence that the ghrelin-GHS-R axis is involved in prostate cancer, as prostate cancer cell lines produce both ghrelin and the receptor through which it acts. Our preliminary studies show that ghrelin enhances cell growth in these cells. GHRH blocking agents (antagonists) are potential treatments for prostate cancer, as they slow the growth of prostate tumours. How they act is unclear, but they might interfere with a locally active GHRH pathway in the prostate. This study aims to explore the role of ghrelin and GHRH in prostate cancer. Since there is an increase in the use of GHRH, GH and-or IGF-I and potentially ghrelin for the treatment of a variety of medical conditions, including some in the aging male, the need for a fuller understanding of the role of this axis in prostate cancer is increasingly important. Such information will lead to a deeper understanding of the actions of ghrelin and GHRH and provide potential opportunities for design of new therapies for prostate and other GH-IGF-responsive tumours.Read moreRead less