Question

Scenario 2: As all avid Tolkien fans know, hobbits are very fond of mushrooms. Merry and Pippin in particular have massive cravings for this specific fungus. One day, while outside and up to no good, Merry and Pippin come across a likely looking patch of mushrooms. Excited the two hobbits quickly collect most of what is available. In their haste they are not as careful to examine the mushrooms they are collecting. Unable to wait for dinner, Pippin decides to snack on some of the mushrooms as the pair head back towards home. About an hour later, Pippin begins to feel odd. Merry notices that Pippin’s pupils are tiny and Pippin is producing more spit when he talks. Pippin also starts sweating heavily even though it is not a hot day. His eyes are watering excessively too. An hour after that Pippin begins to have abdominal cramps. He starts having trouble breathing. After consulting Sam, Frodo’s gardener, both Merry and Pippin learn that the mushrooms they collected are poisonous. In fact these mushrooms contain high levels of muscarine. And as Sam predicts, within a few hours, Pippin is a most miserable hobbit. His abdominal cramps have increased to the point that he is now experiencing both vomiting, excessive urination, and diarrhea. Fortunately for Pippin, he did not consume enough muscarine to kill him. However, he is a very unfortunate hobbit for the next day or two until the drug is cleared from his system.

a. Which part of the autonomic nervous system is being affected by the muscarine? How do you know?

b. Which symptoms can you identify as being a direct result of this system being affected?

c. What organs in the body contain muscarinic receptors?

Answer 1

a. The Parasympathetic Nervous System is being affected by the muscarine as it contains muscarinic receptors, (M1 - M5). In the Sympathetic Nervous System, some receptors are also found in cells of sweat glands. These effects will be known to us by the symptoms presenting such as:

• Cardiac symptoms like bradycardia
• Exocrine gland - Lacrimation, Salivation
• Smooth muscle -  Nausea, vomiting, cramps, diarrhea
• Urinary tract - Incontinence
• Respiratory system - Dyspnea, thick secretions
• Eyes - Obscure vision, diminished vision

Excessive Sweating due to sympathetic stimulation can also be seen.

b.Vomiting, Diarrhea

c. Bladder ( M2, M3)

  Brain ( M1 - M5)

Eye ( M1 - M5)

Heart (M1, M2, M3, M5)