Neuroendocrine Control of Repro

Exocrine Glands

have ducts, secrete externally

Endocrine Glands

no ducts, secrete into the bloodstream

Concentrations of hormones are very…

precise and dependent on the hormone’s job

Episodic Concentration

hormone surges every once and a while and then goes back to baseline

Basal Concentration

a low, constant secretion of hormones

Sustained Concentration

a surge in hormones that remains high

Peptide/Protein Hormones

• Made of amino acids

• Water soluble

• Effectiveness depends on bloodstream administration; CANNOT be taken orally

Steroid Hormones

• Cholesterol is the precursor

• NOT water soluble; can be taken orally

Fatty Acid Hormones

• Biologically active lipids

• DOES NOT fit classic hormone description

• Produced by cells throughout the body NOT endocrine glands

• Acts at the production side → degrades quickly once produced

Primary Reproductive Hormones

regulate reproductive process

Secondary Reproductive Hormones

regulate other physiological processes but also influence the reproductive process

Draw the anatomy of a hypothalamus and explain the process

1. Hypothalamus

2. Nerve cell bodies

3. Hypophyseal portal system

4. anterior pituitary

5. posterior pituitary

6. arteries

GnRH

Gonadotropin-releasing hormone

releases FSH and LH from the anterior pituitary gland.

Surge Center

part of the hypothalamus that sends surges of activity to encourage a surge of hormones

Tonic Center

part of the hypothalamus that sends a basal pattern of activity for a basal pattern of hormones

What is the importance of the Hypophyseal Portal System?

Allows deliveries of hormones without dilution in systemic circulation and allows for rapid response.

FSH

• Follicle-Stimulating Hormone

• Comes from the Anterior Pituitary

• Targets Granulosa Cells (Fe.) and Sertoli Cells (M.)

• stimulates follicle growth, estrogen production (Fe.), sertoli cell production, and Spermiogenesis (M.)

LH

• Luteinizing Hormone

• Comes from Anterior Pituitary

• Targets theca cells and corpus luteum (Fe.) and Leydig Cells (M.).

• Stimulates ovulation, corpus luteum formation, progesterone production (Fe.), and testosterone production (M.).

Oxytocin

• Comes from posterior pituitary

• Peptide

• Produced by Corpus Luteum

• Facilitates CL regression

The posterior pituitary is an _________ of the hypothalamus.

extension

Estrogen

• Steroid

• Produced by Follicles

• Encourages mating behavior

Progesterone

• Steroid

• Produced by Corpus Luteum

• Inhibits mating behavior

Testosterone (for ovarian system)

• steroid

• produced by theca cells

• substrate for estrogen production

Inhibin (in ovarian system)

• Protein

• Produced by Follicles

• Inhibits FSH secretion

Testosterone (in testes system)

• Steroid

• Produced by Leydig Cells

• Encourages mating behavior and spermatogenesis

Inhibin (in testes system)

• Protein

• Produced by Sertoli Cells

• Inhibits FSH secretion

Prostaglandin F2q

• Fatty Acid Hormone

• Contributes to Luteolysis

Prostaglandin E2

• Fatty Acid Hormone

• Contributes to ovulation

Half-Life

rate at which hormone is cleared from circulation

Receptor Density

how many receptors are on a given cell type

Receptor Affinity

how well the receptor binds to the hormone

What are the two “second messengers”?

1. cAMP

2. Ca2+

What happens inside the cell once a hormone binds to the receptor?