Endocrine and Respiratory System: Hormones, Feedback, Lung Diseases

Hormone types

Peptide, steroid, and amine hormones

Receptor location (peptide vs steroid)

Peptide bind to cell membrane receptors; steroid bind intracellularly (cytoplasm/nucleus)

Negative feedback

Output inhibits further hormone release to maintain homeostasis

Positive feedback example

Oxytocin increases contractions during labor

Second messenger system

Intracellular signal (e.g., cAMP) that amplifies hormone effects

Hormone transport

Water-soluble travel free; lipid-soluble are protein-bound

Hypersecretion vs hyposecretion

Too much hormone vs too little hormone production

Pituitary gland function

Master gland that regulates other endocrine glands

Acromegaly cause

Excess growth hormone in adults

Dwarfism cause

Growth hormone deficiency in childhood

Thyroid hormone function (T3/T4)

Regulate metabolism

Hyperthyroidism symptoms

Weight loss, heat intolerance, tachycardia

Hypothyroidism symptoms

Weight gain, cold intolerance, fatigue

Graves disease

Autoimmune hyperthyroidism

Hashimoto's thyroiditis

Autoimmune hypothyroidism

Parathyroid hormone (PTH) function

Raises blood calcium levels

Hyperparathyroidism effect

Hypercalcemia and bone loss

Hypoparathyroidism effect

Hypocalcemia and tetany

Adrenal disorders examples

Cushing syndrome (excess cortisol) and Addison disease (low cortisol)

Type 1 diabetes cause

Autoimmune destruction of beta cells leading to no insulin

Type 2 diabetes cause

Insulin resistance with relative insulin deficiency

Insulin function

Lowers blood glucose by promoting uptake into cells

Hyperglycemia symptoms

Polyuria, polydipsia, polyphagia

Hypoglycemia symptoms

Sweating, confusion, tachycardia

Diabetes complications

Neuropathy, nephropathy, retinopathy

Gas exchange location

Alveoli

Oxygen transport

Oxygen binds to hemoglobin in blood

Ventilation vs perfusion

Ventilation is air movement; perfusion is blood flow

V/Q mismatch

Imbalance between ventilation and perfusion

Obstructive lung disease

Difficulty exhaling air

Asthma cause

Airway inflammation and bronchoconstriction

Asthma symptoms

Wheezing, dyspnea, chest tightness

Chronic bronchitis feature

Productive cough for at least 3 months per year

Emphysema pathophysiology

Alveolar destruction leading to decreased gas exchange

COPD definition

Combination of chronic bronchitis and emphysema

Restrictive lung disease

Reduced lung expansion

Pulmonary fibrosis effect

Stiff lungs with impaired gas exchange

Pneumonia

Alveoli fill with fluid or pus

Tuberculosis cause

Mycobacterium tuberculosis infection

Hypoxemia

Low oxygen levels in blood

Hypercapnia

Elevated carbon dioxide levels in blood

Pulmonary embolism

Blood clot in lung circulation

Pulmonary hypertension

Increased pressure in pulmonary arteries

ARDS

Severe inflammation causing alveolar damage

Atelectasis

Collapse of alveoli

Cyanosis

Bluish skin due to low oxygen

Dyspnea

Difficulty breathing

Spirometry

Measures lung volumes and airflow

FEV1

Forced expiratory volume in one second

Respiratory failure

Inadequate gas exchange of oxygen or carbon dioxide