Pretend you are a teacher preparing a quiz for the text I will provide. 
            Each quiz question should follow the format below. 
            Ensure that you carefully recheck the questions and answers for accuracy. 
            The output should be a ready-to-use list of dictionaries for the Python eval function:

            [

                    "question": "WRITE THE QUESTION HERE",
                    "options": ["A) OPTION_1", "B) OPTION_2", "C) OPTION_3", "D) OPTION_4"],
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            ]

            Text:
            itory 
postsynaptic 
(β2)  
• 
Found in bronchi of the lungs, 
vascular beds, and uterus 
• 
Responsible for bronchodilation 
and vasodilation 
 
 
• 
Table 3.2 illustrates the differences in degrees of α and β receptor activity of three 
commonly used vasoconstrictors. 
 
• 
Table 3.3 lists the systemic effects, based on α and β receptor activity, of 
epinephrine and norepinephrine 
 
Dilutions of Vasoconstrictors  
• 
The dilution of vasoconstrictors is commonly referred to as a ratio (e.g., 1:1000) —
—> because the maximum doses of vasoconstrictors are presented in milligrams, 
or more commonly today in micrograms. 
• 
The milligram per millilitre and microgram per millilitre values of the various 
vasoconstrictor dilutions used in medicine and dentistry are shown in Table 3.4 
 
 
• 
Epinephrine concentration of 1:200,000 provides comparable results, with fewer 
systemic side effects. 
Epinephrine:  
• 
Most used vasoconstrictor in local anaesthetics in both medicine and dentistry. 
• 
It is not an ideal drug and the benefits to be gained from adding epinephrine to a 
local anaesthetic solution must be weighed against any risks. 
• 
Resting plasma epinephrine levels (39 pg/mL) are doubled after administration of 
one cartridge of lidocaine with epinephrine 1:100,000 
• 
Elevation of epinephrine plasma levels persists from several minutes to 30 
minutes after administration and equivalent to those achieved during moderate to 
heavy exercise. 
• 
These are associated with moderate increases in cardiac output and stroke 
volume. 
• 
Blood pressure and heart rate are minimally affected at usual doses. 
• 
In patients with preexisting cardiovascular or thyroid disease, the side effects of 
absorbed epinephrine must be weighed against those of elevated local 
anaesthetic blood levels. 
• 
However, even after usual precautions (e.g., aspiration, slow injection) have been 
taken, sufficient epinephrine can be absorbed to cause sympathomimetic 
reactions (epinephrine reaction) such as:  
1. Apprehension. 
2. Tachycardia. 
3. Sweating. 
4. Palpitation. 
• IV administration of vasoconstrictors produce significant clinical manifestations. 
• Intravenous administration of 0.015 mg of epinephrine with lidocaine results in:  
1. Increase in the heart rate ranging from 25 to 70 beats per minute. 
2. Elevation in systolic blood pressure from 20 to 70 mmHg. 
3. Arrhythmias 
4. Premature ventricular contractions. 
• 
Other vasoconstrictors used in medicine and dentistry include:  
1. norepinephrine:  
• Lacks significant β2 actions. 
• Intense peripheral vasoconstriction. 
• Elevation of blood pressure. 
• Associated with a side effect nine times higher than that of 
epinephrine, therefore its use in dentistry is diminishing and not 
recommended. 
3. 
Levonordefrin: 
• 
The cardiovascular effects of levonordefrin most closely resemble those of 
norepinephrine. 
4. 
Felypressin:  
• 
It’s about as effective as epinephrine in reducing cutaneous blood flow. 
Epine

            Quiz: