Endocrine Signaling Pathways: Hormones and Representative Molecule Insulin

This article discusses the endocrine signaling pathways in the human body, where hormones are produced by endocrine glands and released into the bloodstream. The article focuses on insulin as a representative molecule and its functions in regulating carbohydrate metabolism. The article also explains the role of the insulin receptor in signal transduction.

RUNNING HEAD: ENDOCRINE SIGNALLING PATHWAYS 1
Endocrine signaling pathways
Name:
Institution:
Tutor:
Date:

ENDOCRINE SIGNALLING PATHWAYS 2
Endocrine signaling pathway
Different signals are supposed to be transmitted to different parts of the body. This is
only possible under the help of the circulatory system. Endocrine signaling pathway is therefore
the production of signals by different specialized cells and then released into the bloodstream
(Lynch & Adams, 2014) .It is the blood stream that in return distribute the produced signals to
the different parts of the body. The signals that are secreted in one part of the human body and
then distributed to other parts of the body are known as hormones.
In the human body, hormones are produced by endocrine glands. Examples of glands
include thyroid, hypothalamus, pituitary and the gonads. Each gland has specific hormones that it
releases. The pituitary gland for example releases growth hormones. The function of the growth
hormone is to promote growth. According to different studies, the effects of the endocrine
signaling pathways take place slowly (Cantley, 2014). The studies have linked the slow response
to the long distance that the hormones travel. Another factor that leads to the slow response is the
fact that they are diluted in blood during transportation and the low concentrations therefore
leads to the slow response. This is where the endocrine signaling pathways are different from the
paracrine signaling where the ligands are always in high concentrations. Despite the slow action
of the hormones however, there effects are quite long lasting.
The representative molecule

ENDOCRINE SIGNALLING PATHWAYS 3
The representative molecules in the endocrine signaling pathways are hormones. There
are different hormones in the body but for this assignment, I will use insulin as the representative
molecule in the endocrine signaling pathway. Insulin is a hormone in the body that is produced
by the pancreas. The pancreas has specialized units within which are known as islets of
Langerhans. The islets of Langerhans is also made up of a unit of different cells that are known
as beta cells. It is the beta cells therefore that secrete the hormone insulin (Cantley, 2014). This
hormone is usually released from the pancreas and then distributed to the rest of the body by
blood. The hormone has diverse functions though the most important is the regulation of how the
body utilize carbohydrates. Glucose is the end product of carbohydrates metabolism which is
used by cells as fuel .In the absence of the hormone insulin, the cells might not utilize glucose
and this leads to malfunctioning. Tyrosine kinase is the insulin receptor. Insulin usually bind to
the receptor and passes the message in the cell. The receptor has two copies of the protein chains
that come together to form the receptors site which attach to insulin. This therefore means that
the function of the receptor for insulin is to assist the insulin pass the message into the cells but it
does not take part in the signal transduction.

ENDOCRINE SIGNALLING PATHWAYS 4
References
Cantley, J. (2014). The control of insulin secretion by adipokines: current evidence for
adipocyte-beta cell endocrine signalling in metabolic homeostasis. Mammalian
Genome, 25(9-10), 442-454. doi:10.1007/s00335-014-9538-7
Lynch, C. J., & Adams, S. H. (2014). Branched-chain amino acids in metabolic signalling
and insulin resistance. Nature Reviews Endocrinology, 10(12), 723-736.
doi:10.1038/nrendo.2014.171