Video Transcript
ADH and oxytocin are released by
the posterior pituitary gland. In what structure are they
produced?
This question asks us about
hormones released from the pituitary gland, which is a small gland about the size of
a pea located under the brain. The pituitary gland is divided into
two lobes according to which side of the brain they’re closest to: the anterior or
frontal part of the brain or the posterior lobe, which is located closer to the back
of the brain. Let’s take a closer look at the
pituitary gland so we can see these lobes more clearly.
The two lobes of the pituitary
gland have a different structure and they also function a bit differently. The anterior, or frontal, lobe
contains cells that produce and secrete a wide variety of hormones into the blood
that will modulate the activity of many different tissues in the body. For example, the anterior lobe
produces and releases growth hormones, or GH, that act on our muscles and bones to
stimulate our growth and metabolism.
The anterior lobe also releases
various hormones that are said to be tropic because they can stimulate the release
of other hormones by other endocrine glands, for example, ACTH that stimulates the
adrenal glands. These hormones and many others can
then be transported via the blood to their target cells.
In contrast, the posterior lobe of
the pituitary gland is not a site of production of hormones. It’s rather a site of storage of
hormones. In fact, this part contains the
terminals of specialized neurons that have the capacity to produce hormones that can
then be released into the blood. Some of the hormones that are
released from the posterior pituitary gland include ADH, or antidiuretic hormone,
and a hormone called oxytocin. The cell body of the neurons that
produce these hormones is located in a region of the brain called the
hypothalamus.
Neurons in the hypothalamus process
the information coming from the entire body and the environment, which is why the
hypothalamus is considered a control center that coordinates the nervous system and
the endocrine system. When stimulated, these neurons send
a signal along their axons and to their axon terminals to command the release of
hormones into the blood. Therefore, the answer to this
question that’s asking us where ADH and oxytocin are produced is the
hypothalamus.
