A Case on Nervous Tissue

Case 1: Nursing Homework Help| Nursing homework help

This case study on nerve tissue in fish is a bad one.

Introduce yourself

Tetrodotoxin, or TTX for short, is a powerful neurotoxin present in tissues of the pufferfish. This species is commonly eaten in Asia. Ingesting TTX-contaminated puffer fish can cause symptoms including numbness or paralysis. In this case study, Dr. Marshall Westwood is the subject. He experienced symptoms of numbness and vomiting after eating rice with puffer fish in Indonesia. This paper will examine the signs and symptom of TTX intoxication, the biology and function of nerve cells as well the effects of TTX upon the nervous systems.

Signs and Symptoms Of TTX Intoxication

The term diaphoresis means excessive sweating. In the case of Dr. Westwood, it is possible that the diaphoresis was a result of the body’s physiological response to the toxin, as the body tries to remove the toxin through the skin.

The inability to control muscles can be anything from mild tremors up to total paralysis. In Dr. Westwood’s case, he experienced paralysis that started in his legs and spread to the upper body, arms, face, and head.

The term paresthesia refers to a form of sensory disturbance which can produce sensations including tingling and numbness. Dr. Westwood experienced numbness that spread quickly to his neck, face, and lips.

A lack of oxygen can cause the skin to turn a blueish colour. Hypoventilation is a reduced rate of breathing and reduced depth, which may lead to less oxygen being absorbed by the body. In Dr. Westwood’s case, his cyanotic skin color and hypoventilation suggest that the toxin was affecting his respiratory system, making it difficult for him to breathe.

Bradycardia is a slower heartbeat than usual, in this instance 78 beats per minutes. The toxin can affect the electrical system in the heart, causing the slowing down of heartbeat.

In gastric lavage, the stomach is washed with liquid to eliminate any toxic substances. In Dr. Westwood’s case, gastric lavage was used in an attempt to remove the TTX from his body.

As a percentage, oxygen saturation measures the level of oxygen present in blood. A normal oxygen saturation is between 95-100%, with Dr. Westwood’s oxygen saturation at 97% on room air.

Neuronal Cell Biology

The membranes of nerve cells contain proteins called voltage-gated sodium channels. They are the channels that allow the sodium ions in, causing a change to the electrical potential. The change in electrical voltage is known as an action potential.

Resting membrane potential is due to an unequal distribution between positive and negative charge on each side of the membrane of a neuron cell. Inside the cell, there is a negative charge while outside it is a positive charge. The membrane is electrically charged due to the charge difference.

The voltage-gated sodium channels in a cell open when a cell is stimulated by a chemical or touch signal. This allows sodium ions into the cell. The positive charge influx further depolarizes and makes the cell more positive. A potential for action is produced if the depolarization exceeds a threshold.