Chapter 17.3, Problem 7AYLO

Summary Introduction

To discuss:

Three tissue zones of the adrenal cortex, their hormones, and functions.

Introduction:

The adrenal gland is composed of two glands with different origin of cells and functions. It is located on the superior part of each kidney. The size of the adrenal gland in adult is about 5 cm long and 3 cm wide. In newborns, it weighs nearly 8-10 g; however, half of its weight is reduced at the age of 2 years. Involution causes the shrinkage of this gland, and it remains about 4-5 g in adults. The adrenal medulla and adrenal cortex are the inner and outer portions of the adrenal, respectively. The adrenal medulla secretes epinephrine, norepinephrine, and dopamine (mixtures of catechol amines), whereas the adrenal cortex secretes cortisol and aldosterone into the blood stream. The adrenal gland regulates alertness, metabolism, blood circulation, blood glucose level, and respiration.