Ghrelin: It’s Role in Human Physiology Lucas M. Weikart Neuroscience 2050

1. Abstract In this poster I will be discussing the major influences Ghrelin plays in our bodies. It is primarily responsible for inducing appetite while its counterpart leptin is primarily responsible for suppressing appetite. Research will also be looked at near the end showing how sleep and Ghrelin work together to maintain body mass index measurements. • Summary • Ghrelin was first discovered in 1996 by scientists Masayasu Kojima and Kenji Kangawa while they were searching for a ligand in the brain. Ghre, the proto indo European root, which means to “to grow” fits nicely with the understanding of the neurotransmitter Ghrelin. Ghrelin is a twenty eight amino acid long peptide that functions as a hormone and neurotransmitter protein. It is found primarily in the fundus of the stomach where it is produced and plays a role in gastrointestinal function. Other places ghrelin is found are the Central Nervous System, most notably, the hypothalamus and other organs within the human body. Ghrelin’s mechanism of action begins with production in the small intestine and then proceeds to many other organs of the body where many diverse actions take place. • Hunger • Hunger occurs when Ghrelin is secreted and binds to the Ghrelin receptors when the body is in a negative energy balance. This is when the body is expending more energy then what it has reserved. Appetite occurs in this segment and satiation proceeds. Once satiated leptin increases, suppressing appetite, and Ghrelin levels drop. Ghrelin: It’s Role in Human Physiology Lucas M. Weikart Neuroscience 2050 Lucasweikart@mail.weber.edu Research Discoveries The basis of energy balance can be explained by levels of ghrelin in the human body. Simply put, the more ghrelin circulating inside the body the lower the body weight and vice versa. This data shows us that ghrelin plays a central role in the regulation of body weight. In the following research presented on sleep and obesity, sleep is found to affect ghrelin levels in the human body which may, in turn, affect weight loss or gain .These findings have indicated a direct relationship between levels of ghrelin and hours of sleep. For example, individuals who sleep for five to eight hours a night are found to have a higher BMI than those who get eight or more hours a night. Also, ghrelin levels in those individuals who sleep five to eight hours tend to have higher levels while those who sleep eight hours or more have less. This correlation shows that those who sleep eight hours or more are less likely to have a high BMI as it relates to low levels of ghrelin found in their blood plasma. This encouraging research has shown that ghrelin does play a very influential part in the sleep cycle as it relates human weight.