Endocrine System

Functions of Endocrine System

Regulate a wide range of body functions

through production and secretion of hormones into the bloodstream.

Functions of Endocrine System

Hormones are molecules that have an effect

only on specific cells called target cells which have receptors for that hormone. The organs that contain target cells are called target organs.

Functions of Endocrine System

Body functions regulated

by endocrine system:
•metabolism

•growth and development

•sexual function and reproduction

•heart rate

•blood pressure

•appetite

•sleeping and waking cycles

•body temperature

Organs of Endocrine System

Endocrine glands:

•Pituitary gland

•Thyroid gland

•Parathyroid gland

•Adrenal glands

•(Pineal gland)

Organs of Endocrine System

Organs containing endocrine cells

•Hypothalamus

•Thymus

•Pancreas

•Testes and Ovaries

•(GI Tract, Kidneys, Heart)

Hypothalamus

Master control center

of the endocrine system

Hypothalamus

Controls secretory activity

of anterior pituitary gland

Hypothalamus

Oversees stimulation and

hormone secretion of adrenal medulla

Hypothalamus

Produces hormones to be

released by the posterior pituitary gland:
•Regulatory hormones i.e. Prolactin-releasing hormone

•Antidiuretic hormone (ADH)

•Oxytocin (OT)

Pituitary Gland

Pituitary is also called

the hypophysis

Pituitary Gland

Located just inferior to the

hypothalamus – connected by infundibulum (stalk)

Pituitary Gland

Housed in

sella turcica of sphenoid bone

Pituitary Gland

Divided into

anterior and posterior lobes

Thyroid Gland

Thyroid is largest gland entirely

devoted to endocrine activities

Thyroid Gland

Located inferior to

thyroid cartilage and anterior to the trachea

Thyroid Gland

Butterfly shape

Thyroid Gland

Secretes hormones important for metabolism and calcium balance:

• Thyroid hormone (TH) increases

•metabolic rate (iodine is needed to produce TH)

Thyroid Gland

Secretes hormones important for metabolism and calcium balance:

• Calcitonin reduces

blood calcium

Parathyroid Glands

Essential

endocrine gland

Parathyroid Glands

Four small nodules located

on the posterior surface of the thyroid gland

Parathyroid Glands

Secretes hormones important

for calcium balance

Parathyroid Glands

Parathyroid hormone (PTH) increases

blood calcium levels

  Adrenal Glands
Paired adrenal glands sit on

superior borders of the kidneys

  Adrenal Glands
Each gland has an outer adrenal cortex and an

inner adrenal medulla, with each region secreting different hormones

  Adrenal Glands

Controlled by

anterior pituitary hormones

  Adrenal Glands

Adrenal cortex secretes

corticosteroid hormones that regulate salt, sugar and reproduction

  Adrenal Glands
Adrenal medulla is a modified

sympathetic ganglion that secretes epinephrine (adrenaline) and norepinephrine involved with fight-or-flight response

  Pancreas
Elongated organ situated

posterior to the stomach

  Pancreas
Exocrine cells secrete

alkaline pancreatic juice in small intestine

  Pancreas
Endocrine cells secrete hormones

important for blood glucose levels

  Pancreas

Insulin decreases

blood glucose levels

  Pancreas
Glucagon increases

•blood glucose levels

  Pancreas

Somatostatin slows

down absorption of nutrients

Clinical Anatomy: Hyperthyroidism

Excessive production

of thyroid hormone

  Clinical Anatomy: Hyperthyroidism

Consequences: Increased

metabolic rate, weight loss, hyperactivity, heat intolerance, exophthalmos (bulging eyes)

  Clinical Anatomy: Hyperthyroidism

Cause: Most common cause

is Graves disease (autoimmune disorder)

  Clinical Anatomy: Hyperthyroidism

Treatment: Initial treatment for hyperthyroidism

usually is anti-thyroid medicine or radioactive iodine therapy.

Clinical Anatomy: Hypothyroidism

Decreased production

of thyroid hormone

Clinical Anatomy: Hypothyroidism

Symptoms: Low

metabolic rate, lethargy, being cold, weight gain, photophobia. It can lead to goiter which is the enlargement of the thyroid gland.

Clinical Anatomy: Hypothyroidism

Causes: Caused by lack

of iodine which leads to deficiency of Thyroid hormone or Hashimoto’s disease (autoimmune disease)

Clinical Anatomy: Hypothyroidism

Treatment: oral

thyroid hormones; surgically removal for goiter

  Health Disparities in Thyroid Disease

In the case of benign disease,

•non-White patients are more likely to have delay to referral than White patients.

  Health Disparities in Thyroid Disease

In the case of thyroid cancer,

Black patients are more likely to present with larger tumors, more aggressive forms of thyroid cancer and less likely to have lymph node evaluation than White patients.

  Health Disparities in Thyroid Disease

Overall and disease-specific survival rates

are lower in Black and Hispanic populations when compared to White patients.

  Health Disparities in Thyroid Disease

As with other disparities in health,

more aggressive disease patterns in presentation are likely multifactorial, relating to environmental exposure, lack of resources to seek care, delay in diagnosis, access to treatment options, and possible underlying provider bias.

  Clinical Anatomy: Diabetes

A chronic condition where the body

can not properly regulate blood glucose levels due to problems with insulin, a hormone produced by the pancreas.

  Clinical Anatomy: Diabetes

Type 1 Diabetes (Autoimmune)

usually begins in childhood or adolescence

Type 2 Diabetes (Insulin Resistance)

Often linked to genetics, obesity. and sedentary lifestyle, Common in adults but increasingly in youth.

Gestational Diabetes

Temporary, but increases risk of Type 2 diabetes later:

  Health Disparities in Diabetes

Among U.S. adults aged 18 years or older, age-adjusted data for 2019–2021 indicated the following:

• For both men and women, prevalence of diagnosed diabetes was highest among

American Indian and Alaska Native adults (13.6%), followed by non-Hispanic Black adults (12.1%), adults of Hispanic origin (11.7%), non-Hispanic Asian adults (9.1%) and non-Hispanic White adults (6.9%).

  Health Disparities in Diabetes

Among U.S. adults aged 18 years or older, age-adjusted data for 2019–2021 indicated the following:

• Prevalence varied significantly by education level, which is an indicator of socioeconomic status. Specifically,

13.1% of adults with less than a high school education had diagnosed diabetes versus 9.1% of those with a high school education and 6.9% of those with more than a high school education.

  Racism Causes Health Disparities

Historical discriminatory housing and lending policies resulted

in racial residential segregation and neighborhoods with inadequate housing, healthy food access, and educational resources, setting the foundation for the social determinants of health (SDOH) contributing to present-day disparities.

  Racism Causes Health Disparities

Racism in the healthcare system perpetuates health disparities through:

• unequal access and

quality of health services (healthcare provider biases,insurance cost, patient distrust of medical systems, etc)

 
Racism Causes Health Disparities

Racism in the healthcare system perpetuates health disparities through:

• inadequate representation of health professionals
  
  

from racial/ethnic minority groups

  Racism Causes Health Disparities

Racism in the healthcare system perpetuates health disparities through:

• propagation of the erroneous belief that

socially constructed racial/ethnic groups constitute genetically and biologically distinct populations