Neuro Lab Practicum 2

Experimental Neuro

measures how nervous system functions by manipulation/ measuring activity in standard lab conditions; relies on empirical techniques

Theoretical/ Computational

uses models and simulations

Cognitive/ Clinical

measures behavior and mental processes

Molecular Neuro

most elementary level

individual cells that make up neurons and glial cells

DNA, RNA and neurotransmitters

Cellular Neuro

special properties of neuro

characteristics:

neuron types, functions, how they form connections

System Neuro

visual and motor systems

how neurons are wired together to preform a shared functions

Behavioral Neuroscience

Behaviors

specific regions of the brain that are related to specific behavior

Cognitive Neuroscience

Neural Mechanisms: self-awareness, imagination, language

Darwin’s Theory of Evolution

all species come from a common ancestor and share some physiological similarity

Why is studying the brain difficult?

Its unethical to study on live humans

Have to study humans after death

Uses animal models; are quite the same (in genetic makeup and complexity)

How many genes and neurons do humans have?

20,000 genes

billions of neurons

Most common Neuroscience model?

rats and mice

inexpensive, reproduce quickly, share many similar structures with humans

How many genes do mice have?

25,000

How many genes do zebrafish have?

24,000

Why are zebrafish used?

they are transparent, neurons and internal organs are easy to visualize

How many genes do fruit flies have?

15,000

Why are fruit flies better?

simple genome and short life

How many genes and cells and neurons do nematode have?

19,000 genes

1,000 total body cells

302 neurons

Who’s physiology is closet to humans?

Rhesus Monkey

developmental neurobiologist

analzyes the development and maturation of the brain

molecular neurobiologist

uses the genetic material material of neurons to understand the structure and function of the brain molecules

Neuroanatomist

studies the structure of the nervous system

Neurochemist

studies the chemistry of the nervous system

Neuroethologist

studies the neural basis of species-species animal behaviors in natural settings

neuropharmacologist

examines the effects of drugs on the nervous system

neurophysiologist

measures the electrical activity of the nervous system

Physiological psychologist

studies the biological basis of behavior

Psychophysicist

quantitatively measures perceptual abilities

Why is animal testing important?

can be tested to find further unknown information that computers cannot do

Institutional Animal Care and Use Committee (IACUC)

a committee that reviews and approves animal research protocols to ensure ethical and humane treatment of research animals.

Dose = 25 mg/kg BW Cefazolin

Rat body weight = 479 grams = 0.478 kg

Calculate dose to administer:
0.478 kg x 25 mg/kg = 11.95 mg

Calculate volume to inject:
Cefazolin concentration = 100 mg/mL

11.95 mg / 100 mg/mL = 0.12 mL

All antibiotics cross the BBB

false, some antibiotics cannot enter the BBB or CSF due to their molecular size or charge

What antibiotic are animals normally given after surgery?

Cefazolin

What are cell walls made out of?

Peptidoglycan, a polymer consisting of sugars and amino acids, which provides structural support to bacterial cell walls.

Name the stages of anesthesia

1) Analgesia

2) Excitement/ Delirium

3) Surgical Anesthesia

4) Medullary Paralysis

Analgesia

-From start of anesthesia to loss of consciousness

-Normal stats; dream-like state

Excitement/ Delirium

-from loss of consciousness to start of regular breathing

-may vocalize, struggle, respiration, heart and blood pressure may increase

Surgical Anesthesia

-From beginning of regular respiration to stopping of respiration

-Plane 1: spontaneous respiration, loss of eyelid and conjunctival reflex

-Plane 2: intermittent stopping of respiration, loss of corneal and laryngeal reflex

-Plane 3: Loss of function of intercostal and abdominal muscles, loss of pupillary light reflex. True surgical anesthesia

-Plane 4: Irregular respiration, loss of diaphragm function, apnea, loss of cranial reflex

Medullary Paralysis

-From stopping respiration until circulatory failure and death

-Anestetic overdose

What is Consciousness and what is it made up of?

regulated by a network of brain regions rather than a single structure. The key areas include the cerebral cortex, thalamus, and brainstem reticular formation, which work together to maintain awareness and arousal.

What areas are responsible for high-order awareness, perception and decision making?

The cerebral cortex, especially the prefrontal, parietal, and temporal association areas

What does the Thalamus do?

central relay that integrates sensory input and maintains communication between cortical regions. Disruption of thalamocortical signaling leads to loss of consciousness, as seen in deep anesthesia or coma.

Damage causes loss of consciousness

What is the Reticular activating system critical for?

arousal; releases acetylcholine, norepinephrine, serotonin, and dopamine that keep the cortex active and responsive

Damages cause less wakefulness/ awareness

Consciousness is dependent on what?

continuous signaling between the brainstem (which controls arousal), the thalamus (which integrates and distributes signals), and the cerebral cortex (which generates awareness and cognition).

What does anesthesia do in the brain?

altering ion channel activity and synaptic transmission

increases GABA receptors

decreases transmission of glutamate receptors like NMDA and AMPA

Ketamine and nitrous oxide do what?

suppressing cortical and thalamic excitatory circuits

violate isoflurane; increases potassium and decreases sodium and calcium channels

Sodium pentobarbital does what?

anesthetic that acts as a potent central nervous system depressant through its interaction with GABA-A receptors

causes hyperpolarization

high amounts can increase GABA without it even being present

Name the gauges and its associated color

30G → light yellow

26G → brown

25G → orange

24G → purple

23G → blue

22G → black

21G → green

20G → yellow

19G →.creamy yellow

18G → pink

16G → white

Is 26G or 18G bigger?

18G

What is the bevel?

tip of the hypodermic needle

always faces up

What angle is intramuscular?

90 degrees

in muscle

What angle is subcutaneous?

45 degrees

in fat

What angle is intravenous?

25 degrees

in vein

What angle is intredekmal?

10-15 degrees

in skins surface

Name each layer

epidermis

dermis

subcutaneous tissue

muscle

Is drug absorbed faster in fat or muscle?

Drug is absorbed faster in muscle/vein rather than fat due to blood flow

Name instrument and purpose

Hemostatic forceps (hemostat)

clamp blood vessels and stop bleeding

Name instrument and purpose

iris scissors

cutting

Name instrument and purpose

needle driver

to hold needles while suturing

Name instrument and purpose

thumb forceps

to grasp and hold tissue

Name instrument and purpose

bone cutting forceps

cutting bone

rongeur

to remove bone

Name instrument and purpose

suture needles

stitching

Name instrument pieces in order

1) Jaws

2) Joint

3) Shank

4) Rachet

5) Ring

6) Jaw insert

Difference between absorbable and nonabsorbable sutures

Absorbable are made of cat gut and uses on internal organs and slowly dossolve

nonabsorable is made of silk, nylon, polypropylene, and polyester, must be removed later and are used for skin or areas requiring long-term support

What determines the size of a suture?

1-2 without zeros are thicker while 6-0 and 7-0 are fine sutures for nerves

simple continuous suture

single strand of suture material passed back and forth along the incision

simple interrupted suture

most basic and widely used pattern. Each stitch is tied individually, which provides strong closure and allows for adjustment of tension at each point. If one stitch fails, the others still hold.

horizontal mattress suture

greater strength across the incision and helps distribute tension over a wider area of tissue. It is often used in areas where skin edges are under more tension.

vertical mattress suture

both deep and superficial closure in one stitch, helping to evert wound edges and promote better healing. It is useful in thicker tissue or where precise edge alignment is needed.

Ford interlocking suture

lock stitch, resembles the simple continuous pattern but includes small loops that lock each pass in place. This provides extra security while still being relatively quick to place.

running subcutaneous suture

placed beneath the skin surface to close deeper tissue layers or to produce a more cosmetic closure.

proper scrubbing techniques

1) apply soap to the palm of hand

2) dip fingertips of other hand and decontaminate area under nails

3) spread remaining solution from wrist to elbow

4) apply in circular movement until forearm is covered

5) covers all aspects of hands, up to wrists

6) rub backs of hands and palms

7) interlace fingers to reach interdigital spaces and apply to thumbs

8) Allow hands to dry before donning gloves and gown

What and why are the anesthetic gases used in animal surgeries?

isoflurane or halothane

instantly control the flow

Proper scrubbing surgical site technique

Scrub incision with chlorohexidine, starting and the midline, then left then right side, only swiping from top to down, not rubbing

Repeat same steps with povidone-iodine

What does Chlorhexidine do?

broad-spectrum antiseptic that destroys bacteria

What does Povidone-iodine do?

releases free iodine, which rapidly penetrates and oxidizes microbial proteins, killing bacteria, viruses, fungi, and some spores.

how to identify a question and form a hypothesis

-Observe and identify a specific question

• Review what is already known

• Focus the question so it is testable

• Predict an outcome (form a hypothesis)

• Make sure the hypothesis can be
    demonstrated or rejected

control group

the group that does not receive the experimental treatment, used for comparison

cofound

unintended variable that changes along with the independent variable and therefore could provide an alternative explanation for the results

How to chose a sample of animals

select animals that reflect the general characteristics of the population so that the results can be generalized beyond the specific individuals tested. What is observed in that group is assumed to reflect how most animals of the same species would respond under similar conditions

Variation

natural differences that exist among individuals within a population. No two animals are exactly the same

What is a power analysis?

statistical calculation that estimates how many animals are needed to detect a meaningful difference between groups with a given level of confidence

Randomization

Randomization means that each animal has an equal chance of receiving any of the treatment

Replication

repeating the experiment or having multiple animals within each group so that results can be verified and not attributed to chance.

random number table

list of digits arranged in no predictable order, often generated by a computer or mathematical algorithm

assigns randomly for certain uses (1-no dose 4- high dose)

read in order

induced disease

most widely used

reproduce symptoms & biological changes

pharmacological (induced disease)

injecting chemicals

lesion (induced disease)

damaging certain brain region

stress (induced disease)

expose to high stress to activate hypothalamic-pituitary-adrenal

studies mental health issues

biological (induced disease)

injecting bacteria and viruses

spontaneous change

natural biological changes without any stimulation

genetically modified animals

adding, removing or editing specific genes

negative model

resistant to diseases that affect other species

healthy animals

gain baseline data

between subjects

different groups get different treatments

Within-subjects

same animals used across all conditions

Factorial

tests effects of two or more variables

Repeated-measures

measures the same subjects over time

Mixed

combines between- and within-subjects approaches