Anatomy & Physiology Lab 2 Practicum I

It accelerates the rate of protein synthesis, this way stimulating cell growth

Growth Hormone

Triggers the release of thyroid hormones

Thyroid Stimulating Hormone

Stimulates  the Adrenal Cortex to release Glucocorticoids, hormones that affect glucose metabolism

Adrenocorticotropic Hormone

In females it targets the ovary promoting follicle development and estrogen production.  In males it targets testicular sustentacular cells promoting sperm cells maturation.

Follicle Stimulating Hormone

In females it induces ovulation and stimulates the production of estrogen and progestins.  In males it stimulates testicular interstitial cells to produce androgens

Luteinizing Hormone

Stimulates mammary gland development; during pregnancy and nursing it stimulates the production of milk. In males it probably helps regulate androgen production

Prolactin

Secreted by the pars intermedia, stimulates melanocytes to increase the synthesis of melanin.  The Pars intermedia becomes virtually non-functional in late adulthood

Melanocyte-Stimulating Hormone

Reduces water lost through the kidneys , reducing ions concentrations in plasma.  In high concentration it also produces vasoconstriction leading to increase  in blood pressure

Antidiuretic Hormone

In women it stimulates uterine muscle to contract for labor and delivery.  After delivery it promotes the ejection of milk from the mammary glands.  In males it stimulates ejaculatory ducts, prostate and seminal vesicles for sperm emission, prior to ejaculation

Oxytocin

Secretes mineralocorticoids, the most relevant is Aldosterone(ADH) , it causes retention of sodium ions at the kidneys and exocrine glands (sweat/salivary, pancreas).  Retention of Na+ is paired by lost of potassium.  Water is also osmotically reabsorbed at the kidneys. The outermost cortical region consists of dark-stained cells arranged in oval clusters

Zona Glomerulosa

Secretes glucocorticoids , mainly Cortisol, under ACTH stimulus.  Cortisol has antiinflammatory effect by inhibiting mediators of this reaction in the immune system. It also promotes  the synthesis of glycogen in the liver and the release of fatty acids from adipose tissue into the blood and other tissues.  On the down side it decreases the rate of wound healing and also weakens the reaction of the immune system against infectious agents. Made up of larger cells arranged in tight columns.  These cells appear lightly colored due to their large lipid content

Zona Fasciculata

Under stimulus by ACTH, both in males and females, it secretes small quantities of Androgens, the sex hormones normally produced in large amount by the testes in males.  Once in the blood stream, some androgens convert to estrogens, the dominant sex hormone in females.  Adrenal androgens trigger the development of sexual hair patterns in pre-puberal girls and boys .

While not important in adult men, in adult women adrenal androgens promote muscle mass, (anabolic effect), hemopoiesis and support the libido.

Zona Reticularis

Regulated by sympathetic hypothalamic neurons

In times of stress, exercise or emotions, the hypothalamus stimulates the adrenal medulla to release the neurotransmitters epinephrine and norepinephrine into the blood, resulting in a body wide sympathetic fight-or-flight response

Adrenal Medulla

Are both secreted by thyroid follicular cells

Thyroid Hormone (T3, T4)

Responsible for most of the observed effects of the thyroid hormones

T3 (Triiodothyronine)

Usually circulating at higher levels, is converted to T3 by liver and renal enzymes

T4 (Thyroxine)

Secrete Glucagon, which raises blood sugar level by catabolizing glycogen to glucose (glycogenolysis)

Alpha Cells

Secrete Insulin, which lowers sugar level concentration by accelerating the uptake of glucose by cells and promoting the storage of glucose in the liver and adipose tissue (glyconeogenesis)

Beta Cells