Section 10.1 General Endocrinology

The half lives of hormones differ with some having very short half lives of less than a few minutes e.g. ACTH, epinephrine and nor-epinephrine, with other hormones e.g., erythropoietin having half lives of about 2-3 h in the mouse and 8-lOh in the dog. (see Woodman,1997 and Reimers,1999 for detailed descriptions of animal hormone structures and properties). The binding of circulating T3 and T4 to plasma proteins differs, and for the hormones that are bound to plasma proteins, any factors affecting protein synthesis and the ratio of freedotal hormone levels must be considered when interpreting data. 

Hormones are found in several tissues and organs including  

Some Primary Hormones of Interest and Their Actions 

Endocrine Gland Hormones Target Organ Main Actions 

Hypothalamus Releasing or inhibiting hormones CRH, FRH, GnRH, LRH, SRH, STH, TRH, PIH, PRH Anterior pituitary Control of the production and release of other hormones 

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