Common Aspects of Neural and Endocrine Regulation

The fact that endocrine regulation is chemical in nature might lead one to believe that it differs fundamentally from neural control systems that depend on the electrical properties of cells. This assumption is incorrect. As explained in chapter 7, electrical nerve impulses are, in fact, chemical events produced by the

Table 11.3

Conversion of Prehormones into Biologically Active Derivatives

Endocrine Gland

Prehormone

Active Products

Comments

Skin

Vitamin D3

i,25-Dihydroxyvitamin D3

Conversion (through hydroxylation reactions) occurs in the liver and the kidneys.

Testes

Testosterone

Dihydrotestosterone (DHT) Estradiol-i7ß (E2)

DHT and other 5a-reduced androgens are formed in most androgen-dependent tissue.

E2 is formed in the brain from testosterone, where it is believed to affect both endocrine function and behavior; small amounts of E2 are also produced in the testes.

Thyroid

Thyroxine (T4)

Triiodothyronine (T3)

Conversion of T4 to T3 occurs in almost all tissues.

Was this article helpful?

0 -1
100 Hair Growth Tips

100 Hair Growth Tips

100 Hair Growth Tips EVERY Balding Person Should Know. This Report

Get My Free Ebook


Post a comment