Nerve Tissue (Pawlina Chapter 12)
These neurons convey pain, temperature, touch, and pressure from the body surface, plus pain and proprioception from muscles/tendons/joints
What are sensory neurons?
The neurotransmitter that all preganglionic neurons of the autonomic nervous system release (Both sympathetic and parasympathetic)
Acetylcholine
Fatty Acids
Secreted by pancreatic alpha cells in response to low blood sugar and is suppressed by elevated blood glucose and insulin
Glucagon
Secreted by parietal cells, this inactivates alpha-amylase secreted by the mouth
Hydrochloric Acid (HCl)
The three autonomic nervous system internal organ effectors
Blocks the nicotinic receptor in the ganglia but does not block the nicotinic receptor at the motor end plate
What is Hexamethonium?
List 2 things that can increase BMR
Fever, Hyperthyroidism, Muscle Mass, Pregnancy/Lactation and Colder Climates
Name 2 adrenergic and 2 neuroglycopenic manifestations of severe hypoglycemia
Adrenergic: Diaphoresis, tremors, tachycardia, palpitations, anxiety, and hunger
Neuroglycopenic: Confusion, dizziness, headache, slurred speech, lethargy and seizures
A 28-year-old female presents to the clinic complaining of severe flatulence, abdominal distention, and frequent watery stools after drinking milk. An unabsorbed disaccharide passes into the large intestine, where it undergoes bacterial fermentation. Name one of the products formed by colonic bacterial metabolism of undigested carbohydrates.
Lactic acid, short-chain fatty acids, and gases (H2,CO2,CH4)
This intermediate filament protein is used as a marker for neural stem cells located in the olfactory bulb and the dentate gyrus of the hippocampus
What is nestin?
A medical student is reviewing autonomic nervous system pathways. Which anatomical feature or pathway represents a unique exception to the classic two-neuron chain of the sympathetic division?
Direct preganglionic sympathetic innervation of chromaffin cells in the adrenal medulla
A child in an impoverished area is brought into a free clinic. The child has a prominent "potbelly," peripheral edema and "flaky paint" dermatitis. The child's diet consists almost exclusively of rice. Which of the following best describes the pathophysiological mechanism responsible for this child's clinical presentation?
Kwashiorkor (decreased hepatic synthesis of plasma albumin due to eating enough calories, but not enough protein)
This channel is effected when an infant has a mutation in their KCNJ11 gene
Potassium ATP channel
A 3-month-old infant is brought to the clinic due to a history of severe developmental delay, microcephaly, and intractable seizures. Genetic testing identifies a mutation in a facilitative glucose transporter located in the endothelial cells of the blood-brain barrier. What transporter is defective in this infant?
GLUT 1
An investigator studies the autonomic control of cardiac rate by applying acetylcholine to an isolated sinoatrial tissue preparation. Which cellular target and effector action are directly modulated by this neurotransmitter?
Purkinjie fibers via muscarinic receptor mediated potassium channels opening
A 9-year-old boy is brought to the emergency department after being bitten by a bat on a camping trip. He later develops hydrophobia, agitation, and seizures, eventually succumbing to encephalomyelitis. Brain autopsy demonstrates diagnostic viral inclusions within the CNS. Which histopathological finding is pathognomonic for this condition?
A 25-year-old vegan strictly avoids all animal products and has not taken dietary supplements for 5 years. She presents with progressive fatigue and paresthesias in her hands and feet. What vitamin is she deficient in?
B12
A 35-year-old male patient is evaluated for severe hypoglycemia. A serum profile is conducted during a perceived sugar low. His profile shows high insulin, high C-peptide and low glucose. Which condition does this profile confirm?
Insulinoma
An 18-year-old female presents for a routine physical exam. She reports that since early childhood she has intentionally avoided eating all fruits, table sugar, and fruit juices. She explains that consuming these foods consistently produces severe abdominal pain, vomiting, tremulousness, sweating, and weakness. Her historical pediatric records show post-feeding irritability, jaundice, and hepatomegaly when fruit juices were first introduced at age 1. Which enzyme deficiencies is most consistent with her condition?
The patient has Hereditary Fructose Intolerance, caused by a deficiency of Aldolase B.
A 32-year-old female presents with episodic unilateral visual loss, dysmetria, and urinary incontinence. MRI reveals multiple demyelinating plaques within the central nervous system white matter. Autoantibodies against myelin basic protein are detected. Which of the following glial cells is primarily targeted in this patient’s disease, and what is its developmental origin?
Oligodendrocyte; Neural tube
A 25 year old is about to go on a cruise, but is concerned about getting motion sickness. What medication would a provider prescribe and what type of receptors does it block?
What is scopolamine and cholinergic muscarinic receptors?
A 51-year-old patient comes into the ER at the insistence of his wife. His wife is concerned about chest pain, swelling (edema), his weight loss, short term memory loss, and muscle weakness. The patient admits to struggling with excessive alcohol consumption. An echocardiogram and radiograph reveal cardiomegaly. What deficiency does this patient have and what condition has it lead to?
Thiamine and Beriberi (wet)
A 14-year-old male presents with persistent mild hyperglycemia noted on routine laboratory screening. His father and paternal grandfather had similar asymptomatic mild elevations in blood glucose throughout their lives. Genetic testing reveals a heterozygous loss-of-function mutation in the gene encoding pancreatic glucokinase. What should the patient be diagnosed with and how is it inherited?
Maturity- Onset Diabetes of the Young (MODY)
Autosomal Dominant
A 22-year-old collegiate athlete completes a high-intensity 400-meter sprint. During the sprint, her skeletal muscles rely heavily on anaerobic glycolysis, converting pyruvate to lactate. Following exercise, lactate is transported through the bloodstream to the liver, where it is converted back to pyruvate and subsequently used to synthesize glucose via gluconeogenesis. The newly formed glucose is released back into the blood to be utilized by peripheral tissues. This inter-organ metabolic loop is known as what?
Cori Cycle