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Flashcards in Module 2 Deck (234)
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1

Blocks release of Ach from presynaptic terminals

Botulinum toxin (botox)

2

a drug that blocks the gating action of Ach on the Ach channels by competing for ACh receptor sites on motor end plate

Curare

3

Inhibits acetylcholinesterase

Neostigmine

4

Blocks reuptake of choline into presynaptic terminal

Hemicholinium

5

Antibody directed against the ACh receptor

Myasthenia gravis

6

What is the effect of AChE inhibitor?

Blocks the degradation of ACh, causing an increase in the endplate potential, and prolongs the action of ACh at the motor endplate

7

- A neuromuscular disease with classic symptoms of weakness and fatigue of skeletal muscles
- Seen more commonly in females, with peak incidence at 20 to 30 years of age
- Men have a peak of incidence at around 50 to 60 years of age

Myasthenia gravis

8

Classic symptoms of this disease is muscle weakness that increases with repetitive muscle use (eg, chewing) and partially recovers with rest

Myasthenia gravis

9

- Most common muscular dystrophy
- 1 in 3500 boys (3-5 yo)
- Severe muscle wasting
- Most patients are wheelchair bound by the age of 12
- Respiratory failure in adulthood (30 to 40 years of age)

Duchenne's muscular dystrophy

10

What is gower's sign for Duchenne's muscular dystrophy?

Using hands to push on legs to stand

11

- X-linked recessive
- Defect in the dystrophin gene --> deficiency of the dystrophin protein in skeletal muscle, brain, retina, and smooth muscle

Duchenne's muscular dystrophy

12

- A large (427 kDa) protein present in low abundance (0.025%) in skeletal muscle
- Localized on the intracellular surface of the sarcolemma in association with several integral membrane glycoproteins (forming a dystrophin-glycoprotein complex)

Dystrophin

13

- Tethers Myosin to Z lines (scaffolding)
- Binds Z lines to M line
-largest protein

Titin

14

- Attaches to plasmalemma
- Stabilizes plasmalemma and prevents contraction-induced rupture

Dystrophin

15

Binds Actin to Z lines

Actinin and Capz Protein

16

Binds Z lines to plasma membrane

Desmin

17

- Occurs when contracting muscles are stretched and lengthened too vigorously
- More pain and stiffness than in not-so-vigorous muscle stretching and lengthening (cycling)
Resultant dull, aching pain develops slowly and reaches peak in 24 to 48 hours

Delayed-onset Muscle Soreness

18

- Pain associated with reduced range of motion, stiffness, and weakness of the affected muscles
- Pain due to inflammation near myotendinous junctions
- Slow recovery, depends on regeneration of the injured sarcomeres

Delayed-onset Muscle Soreness

19

- A state of contracture several hours after death
- All the muscles of the body go contraction and become rigid even without action potentials

Rigor Mortis

20

Rigor Mortis results from loss of all the ATP. Why?

It is required to cause separation of the cross-bridges from the actin filaments during the relaxation process

21

- Muscles remain in rigor until the proteins deteriorate (15 to 25 h later)
- All these events occur more rapidly at higher temperatures

Rigor Mortis

22

exert opposite effects but operate reciprocally (complementary) or synergistically to produce coordinated responses

Dual Innervation

23

Single Innervation that has sympathetic only

- sweat glands
- adrenal glands
- most blood vessels
- pilomotor muscle

24

Single Innervation that has parasympathetic only

- lacrimal muscle (tear glands)
- ciliary muscle (accommodation for near vision)

25

2 reasons why adrenal medulla is considered to be part of the ANS

- Nerve supply to AM is anatomically and biochemically identical to autonomic preganglionic nerve fibers
- Adrenomedullary cells are embryologically, anatomically and functionally identical to postganglionic autonomic nerve fibers

26

2 reasons why adrenal medulla is considered a component of SNS and not PSNS

- Origin of nerve supply of AM is thoracolumbar
- Adrenomedullary cells secrete catecholamines (Epinephrine – 80%; Norepinephrine – 20%, the neurotransmitter of sympathetic nerves)

27

- mydriasis
- increased ABP
- vasoconstriction
- increased in skeletal muscle strength
- increased ventilation

Responses of the Sympathetic Nervous System

28

- decreased GIT activity
- elevation of plasma glucose and fatty acid levels
- increase in mental activity

Responses of the Sympathetic Nervous System

29

- lowers threshold in the reticular formation
- redistribution of blood from skin and splanchnic regions towards skeletal muscle

Responses of the Sympathetic Nervous System

30

location:
- radial muscle of iris
- blood vessels of skin, skeletal muscle, splanchnic region
- sphincters of GIT and bladder
mechanism of action:
- activate phospholipase C and increase the intracellular concentration of IP3

Alpha 1 Receptors