Hormones Secreted by Pars Intermedia of Hypophysis

The pars intermedia is a region within the pituitary gland, also known as the hypophysis. It lies between the anterior lobe (pars distalis) and the posterior lobe (pars nervosa) of the pituitary gland. The pars intermedia is responsible for the secretion of various hormones, including Melanocyte-Stimulating Hormone (MSH).

Melanocyte-Stimulating Hormone (MSH)

The correct answer to the given question is option 'C' - MSH. MSH is a hormone secreted by the pars intermedia of the hypophysis. It plays a crucial role in regulating skin pigmentation and melanin production.

Explanation:

1. Pars Intermedia:

The pars intermedia is a region of the pituitary gland that lies between the anterior and posterior lobes. It consists of a mixture of cells that secrete different hormones.

2. Melanocyte-Stimulating Hormone (MSH):

MSH is a peptide hormone that is primarily responsible for regulating pigmentation in the body. It stimulates the production and release of melanin, the pigment responsible for the color of the skin, hair, and eyes. MSH acts on melanocytes, the cells that produce melanin, and stimulates them to produce more melanin.

3. Regulation of Melanin Production:

The production of melanin is regulated by various factors, including exposure to sunlight, genetic factors, and hormonal control. MSH is one of the hormones involved in this process. When the skin is exposed to sunlight, the production of MSH is stimulated, leading to an increase in melanin production. This increase in melanin helps protect the skin from the harmful effects of UV radiation.

4. Other Functions of MSH:

Apart from its role in regulating pigmentation, MSH also has other functions in the body. It has been found to play a role in appetite regulation, immune system modulation, and anti-inflammatory effects. However, its primary function remains the regulation of skin pigmentation.

Conclusion:

In conclusion, the hormone secreted by the pars intermedia of the hypophysis is Melanocyte-Stimulating Hormone (MSH). MSH is involved in the regulation of skin pigmentation and melanin production. It acts on melanocytes to stimulate the production of melanin, which determines the color of the skin, hair, and eyes.