Whole Mount Staining Lab Report

Title The electrophysiological experiment of compound action potentials in bullfrog sciatic nerve trunk. Purpose: Measure the conduction velocity of the sciatic nerve in a bullfrog. Determine the effect of procaine on the conduction velocity of the sciatic nerve. Observe the effect of procaine on the shape of the compound action potential.

We then, placed the subject into an induction chamber until he was properly anesthetized. We the shaved the top of the rat’s head with an electric razor and thoroughly cleaned the shaved area with Septisol solution. We placed the subject in the induction chamber once more and then Dr. Basham used the ear bars to situate the rat in the stereotaxic device. We then placed the vaporizer tubing near the subject’s nose, however, this was not enough to keep him anesthetized so we also decreased the O2 tank pressure, increased the isoflurane concentration to 5% and placed a piece of gauze that was damp with liquid isoflurane near his nose. Once sure of his proper anesthetization, we made a one inch incision from in between his eyes to in between his ears. We squirted some lidocaine into the incision and waited 30 seconds. Then we cleared away the fascia with a cotton swab so we could locate bregma. We positioned the stereotaxic devices needle at bregma and made calculations based off of the atlas coordinates to find the subjects left substantia nigra pathway. We positioned the stereotaxic devices needle 41.8mm in the Anterior- posterior and 35.4mm medial-laterally. I then drilled a small hole in the skull at these coordinates. This drilling hit an intracranial blood vessel and we had to apply pressure and wait for the bleeding to cease. We lowered the needle filled with 6-OHDA down 26.0mm dorsal-ventrally and injected 0.5 microliters every minute for 8 minutes. After this was complete, we removed the needle and with 4 staples, stapled the incision closed. We then removed the subject from the stereotaxic device and placed him back in his cage under a warm light. He woke up within the next couple of

In the mix of the newly formed neural pathways are pathways that aren’t all accountable for pain transmission. These neurons sprout into the dorsal horn, an area that transfers nociceptive afferent inputs, causing central sensitization. Central sensitization is the expansion of neuronal fields and excitability in a certain region of the body. Different neurotransmitters like substance P, neurokinins, and tachykinins conciliate an increase of activity at receptors important for controlling synaptic plasticity, known as NMDA receptors. Following this is a change in firing patterns of central nociceptive neurons, known as the “windup affect.” According to Jenson Nikolajsen (2001), stump or phantom pain in human amputees can be evoked by monotonous stimulation at the location of the stump. The “windup phenomenon” may cause a decrease in the intersegmental inhibitory devices at the level of the spinal cord. This results in spinal disinhibition and nociceptive inputs extending to supra spinal areas. (Subedi & Grossberg, 2011, pg. 2). This may be another potential cause for phantom limb pain due to the absence of afferent involvement and deviations at the level of the spinal cord (Subedi & Grossberg, 2011, pg.

b. Detached axon segments remain attached for a few days after nerve injury (Rotshenker, S., 2011).

Male Wistar rats (3 months old, weighing 280-300g) were used throughout this study. Rats were housed in groups of 3-4 and kept under standard conditions of temperature (22°C ±2) and humidity (40-50%). A 12-h light/dark cycle was provided and animals had ad libitum access to food and water. For icv injection, the animals were anesthetized by i.p. injection of ketamine-xylazine mixture (100 mg/kg-10 mg/kg, respectively) and fixed in a stereotaxic apparatus. A single injection of STZ (0.5, 1 and 3 mg/kg) or saline was applied into the right lateral ventricle (0.8 mm posterior to bregma, 1.5 mm lateral to the sagittal suture, and 3.6 mm beneath the brain surface). Injection volume was 6 µl. The experiments were carried out in accordance with the National Institute of Health Guide for

Spinal nerves have motor fibers and sensory fibers. The motor fibers innervate certain muscles, while the sensory fibers innervate certain areas of skin. A skin area innervated by the sensory fibers of a single nerve root is known as a dermatome. A group of muscles primarily innervated by the motor fibers of a single nerve root is known as a myotome. Myotomes are necessary for proper motor functioning; making it possible to bend the knee, straighten the elbow, flex fingers, and manipulate other muscle groups. Nerve fibers allowing for the sensation of touch or feeling pain to a corresponding sensory sector of the skin are dermatomes. These nerves originate from the spine and therefore can be useful in spinal injuries to evaluate the level of deficit. Pain, lack of sensation, or abnormal functioning of dermatomes can help pinpoint spinal nerve damage. Each myotome (muscle) and dermatome (region of skin) of the body is supplied by a particular level or section of the spinal cord and by its corresponding spinal nerve. There are eight cervical nerves, twelve thoracic nerves, five

There is no straightforward diagnostic test to determine piriformis syndrome, which causes irritation to the sciatic nerve. Piriformis syndrome is diagnosed primarily from the patient’s signs and symptoms and physical examination. All other possibilities must be ruled out first.

Acids in drinks factors in staining teeth. Tooth enamel contains microscopic pits that have the ability to hold particles of food and drinks. The dark color in tea, coffee, soda, and grape juice gives the yellow color on the teeth. Tannins are an ingredient in coffee and tea and more beverages. Tannins cause color compounds more readily stick to teeth. I used eggshells to replace actual teeth because eggshells and teeth are similar. Egg shells are made up of compounds of calcium carbonate. Tooth enamel is composed of calcium phosphate.

Review the L1-5 and S1 dermatomes and muscle group/reflexes used to test for affected nerve roots.

Nerve roots way out between the vertebrae along the length of the spine in the way made by the plates. Harm to the circles or de-hydration/degeneration of the plates can bring about nerve root capture, or what is usually called a squeezed nerve. Since the nerves stretch out into the body there can be torment that emanates into furthest points. Through the expanded hydration to the plates amid reversal the circles stout in tallness, successfully expanding partition between the vertebras and lessening the weight and squeezing on nerve

After seeing how close to the humerus the radial nerve ran, it was easy to understand how mid shaft injuries can lead to radial nerve damage. Not only this, but although we had learnt about the passing of Flexor Digitorum Profundus through Flexor Digitorum Superficialis, it was amazing to see it in real life, it was actually one of the highlights of this dissection for me.

The injuries of nervous system affect many people every year and is estimated that spinal cord injuries alone affect 10,000 each year. Nerve regeneration can be achieved by production of new neurons, glia, axons, myelin, or synapses. There are differences between the functional mechanisms of peripheral nervous system (PNS) and the central nervous system (CNS). PNS has an intrinsic ability for repair and regeneration while CNS usually is incapable of self-repair and regeneration. There is currently no treatment for recovering human nerve function after injury to the CNS. Although, PNS has self-regeneration capacity, much research still needs to be performed for optimizing the environment for maximum regrowth. Injury to PNS immediately elicits the migration of phagocytes, Schwann cells, and macrophages to the lesion site in order to clear away debris such as damaged tissue [56-60].

Patient's complaints regarding weakness or lack of sensation often are rationalized as generalized sequel of the burn injury and healing process. However, these symptoms may be due to peripheral neuropathies and entrapment syndromes resulting from impaired nerve axons, or myelin sheath or both (7). Mononeuropathies and entrapment syndromes have been observed following thermal injury and most often affect nerves under the area of the burn, and they are usually seen in patient with burn greater than 20% of total body surface area (TBSA) (8).

This report represents my individual effort. I did not receive or offer aid to anyone when performing this assignment, nor did I plagiarize any material.

Two hours after formalin stimulation, rats pretreated intrathecally by either Amylin or Salmon Calcitonin showed lower numbers of c-Fos immunoreactive nuclei in their lumbar spinal cord as compared to rats pretreated by saline. These effects were reversed upon co-administration of either of the Amylin antagonists AC187 or rat amylin8-37, but not rat α-CGRP8-37. Few cells with c-Fos immunreactivity were found in the lumbar spinal cord of rats two hours after i.t. injection of saline, Amylin and/or Salmon Calcitonin. However, Fos like immunoreactivity was increased in the lumbar spinal cord two hours after i.t. treatment of either of the antagonists AC187 and rat amylin8-37when compared to saline treated rats.