Exam 3 Review Notes Blood Brain Barrier and CNS Protection

These flashcards cover key concepts related to the Blood Brain Barrier, CNS protection, neurological functions, pain mechanisms, and various pathologies associated with the central nervous system.

What is the primary function of the Blood Brain Barrier (BBB)?

To inhibit potentially harmful substances in the blood from entering the interstitial spaces of the brain or CSF.

What types of cells comprise the Blood Brain Barrier?

Endothelial cells with intracellular tight junctions.

What support cells are involved in the Blood Brain Barrier?

Astrocytes, pericytes, and microglia.

What substances can readily cross the Blood Brain Barrier?

Glucose, lipid-soluble molecules, electrolytes, and certain chemicals via transport molecules.

What happens to the permeability of the BBB with aging?

The BBB becomes more permeable.

What neurological conditions can result from a breakdown of the Blood Brain Barrier?

Neuroinflammation and neurodegeneration.

What is the Reticular Activating System (RAS) responsible for?

Maintaining wakefulness and attention (consciousness) and controlling vital reflexes.

What are the common causes of arousal disorders?

Direct destruction or compression of RAS pathways or impaired blood supply.

What is cerebrospinal fluid (CSF) and its primary function?

A clear, colorless fluid that provides partial protection to brain and spinal cord structures.

What cells produce cerebrospinal fluid?

Ependymal cells in the Choroid Plexus.

How is CSF absorbed into the venous circulation?

Through arachnoid villi in the dura mater.

What are Cheyne-Stokes respirations characterized by?

Alternating periods of hyperventilation and apnea.

What is central neurogenic hyperventilation?

Sustained hyperventilation caused by a lesion stimulating the respiratory center in the central pons.

What is the definition of nociceptor?

Free nerve endings in the PNS responsible for the sensation of pain.

What are the four phases of nociceptive pain?

Transduction, Transmission, Perception, and Modulation.

What is the primary role of endorphins in pain modulation?

To produce a sense of exhilaration and substantial pain relief.

What is MS (Multiple Sclerosis)?

A CNS autoimmune inflammatory disease characterized by the destruction of myelin.

What are the characteristics of migraines?

Classified as with aura, without aura, or chronic, typically have unilateral pain and associated symptoms.

What are the main symptoms of hydrocephalus?

Gradual dizziness, headache, N/V, gait disturbances, and changes in personality.

What tests are used to classify and assess brain injury severity?

The Glasgow Coma Scale and imaging studies.

What is a common cause of cranial nerve palsies?

Damage due to vascular occlusion or tumor.

What are the symptoms of autonomic dysreflexia?

Paroxysmal hypertension, headache, flushing, and bradycardia.

What is the primary common pathogen causing bacterial meningitis?

Streptococcus pneumoniae.

What are the classic clinical signs of meningitis?

Fever, severe headache, nuchal rigidity, Kernig's sign, and Brudzinski's sign.

What is the hallmark of rheumatoid arthritis?

Destruction of synovial joints and the presence of PANNUS.

What causes osteoporosis?

An imbalance between bone resorption and formation leading to reduced bone density.

What is the major hormonal regulator of calcium levels in the blood?

Parathyroid hormone (PTH).