Endocrine System

transmission of direct communication

through gap junctions

transmission of paracrine communication

through extracellular fluid

transmission of endocrine communcation

through the circulatory system

transmission of synaptic communication

across synaptic clefts

chemical mediators of direct

ions, small solutes, lipid-soluble materials

chemical mediators of paracrine

cytokines (paracrine factors)

chemical mediators of endocrine

hormones

chemical mediators of synaptic

neurotransmitters

distribution of direct

usually limited to adajcent cells of the same type (interconnected by connexons)

distribution of paracrine

primarily limited to local area (where there are relatively high concentrations)

distribution of endocrine

target cells primarily in other tissues and organs

distribution of synaptic

limited to very specific area

nervous performs _____ while endocrine regulates _____

short term crisis management; long term ongoing metabolism

what are the types of hormone groups

amino acid derivatives

peptide hormone

lipid derivatives

adenohypophysis and neurohypophysis

anterior and posterior hypophysis

hypophyseal portal system

hypothalamus releases two types of hormones

releasing and inhibiting hormones

adenohypophysis releases

growth (STH)

adrenocorticotrophic (ACTH)

prolactin (LTH)

gonadotropic (FSH, LH)

thyroid stimulating (TSH)

MSH

neurohypophysis releases

oxytocin

antidiuretic (ADH)

all seven hormones are created in the

anterior part of the pituitary gland

FSH

ovaries, testes

sperm production, estrogen secretion, ovarian follicles growth

LH

ovulation, maintenance of corpus luteum, testosterone secretion

somatotrophs

secrete GH

thyrotrophs

secrete TSH

gonadotrophs

secrete FSH and LH

lactotrophs

secrete PRL

corticotrophs

secrete ACTH and MSH

paraventricular nucleus produces

oxytocin

supraoptic nucleus produces

antidiuretic hormone (ADH)