Find out how pineal and thyroid glands help us

The article is in continuation to the last article about chemical coordination and integration in the human body. Last time, we have learnt how pituitary gland helps the human body in multiple ways. • The pituitary hormone Vasopressin acts mainly at the kidney and stimulates resorption of water and electrolytes by the distal tubules and […]

The article is in continuation to the last article about chemical coordination and integration in the human body.

Last time, we have learnt how pituitary gland helps the human body in multiple ways.

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• The pituitary hormone Vasopressin acts mainly at the kidney and stimulates resorption of water and electrolytes by the distal tubules and thereby reduces loss of water through urine (diuresis). Hence, it is also called as anti-diuretic hormone (ADH). An impairment affecting synthesis or release of ADH results in a diminished ability of the kidney to conserve water leading to water loss and dehydration. This condition is known as Diabetes Insipidus.

Now, let’s continue discussion with focus on the functions of the Pineal gland and Thyroid gland. The information can be handy for the upcoming government recruitment examinations.

The pineal gland

• The pineal gland is located on the dorsal side of forebrain.
• Pineal secretes a hormone called melatonin.
• Melatonin plays a very important role in the regulation of a 24-hour (diurnal) rhythm of our body. For example, it helps in maintaining the normal rhythms of sleep-wake cycle, body temperature. In addition, melatonin also influences metabolism, pigmentation, the menstrual cycle as well as our defence capability.

The thyroid gland

• The thyroid gland is composed of two lobes which are located on either side of the trachea.
• Both the lobes are interconnected with a thin flap of connective tissue called isthmus.
• The thyroid gland is composed of follicles and stromal tissues.
• Each thyroid follicle is composed of follicular cells, enclosing a cavity.
• These follicular cells synthesise two hormones, tetraiodothyronine or thyroxine (T4) and triiodothyronine (T3).
• Iodine is essential for the normal rate of hormone synthesis in the thyroid.
• Deficiency of iodine in our diet results in hypothyroidism and enlargement of the thyroid gland, commonly called goitre.
• Hypothyroidism during pregnancy causes defective development and maturation of the growing baby leading to stunted growth (cretinism), mental retardation, low intelligence quotient, abnormal skin, deaf-mutism, etc.
• In adult women, hypothyroidism may cause menstrual cycle to become irregular.
• Due to cancer of the thyroid gland or due to development of nodules of the thyroid glands, the rate of synthesis and secretion of the thyroid hormones is increased to abnormal high levels leading to a condition called hyperthyroidism which adversely affects the body physiology.

To be continued…
By Dr. Modala Mallesh
Subject Expert
Palem, Nakrekal, Nalgonda
9989535675