Endocrine System Functions and Hormones Overview

Posted on May 6, 2024 in Biology

PROLACTIN

Secretes milk, estrogen, and progesterone. Inhibits the action of GONADOTROPINS.

Secretion of PRL is inhibited by the hypothalamus through the PRL-inhibiting hormone (PIH).

PRL increases with surgical stress, psychological nipple stimulation, pregnancy, and childbirth.

Regulates lipids and carbohydrates, essential for growth and normal metabolism.

Deficiency leads to physical and mental issues, while excess causes hyperactivity and heat production.

Thyroxine (T4) and triiodothyronine (T3) are synthesized in the colloid by iodination and tyrosine condensation.

Play a dual role in producing germ cells and sex hormones.

Androgens masculinize, while estrogens feminize; both sexes secrete both hormones.

Ovaries also secrete progesterone to prepare the uterus for pregnancy.

Androgens maintain spermatogenesis, while inhibin inhibits FSH secretion.

LH stimulates testosterone secretion, which negatively feeds back on LH secretion.

Sertoli cells and Leydig cells play crucial roles in spermatogenesis and testosterone production.

Essential for life, secretes glucocorticoids and mineralocorticoids.

Glucocorticoids affect metabolism, while mineralocorticoids regulate sodium and water balance.

Aldosterone, cortisol, and androgens are key hormones secreted by the adrenal gland.