1.
Which of the following is/are not true regarding histamines?
Correct Answer
B. They are distantly acting hormones
Explanation
THey are LOcALLY acting hormones! :)
2.
WHich of teh following cuases a release of histamine?
Correct Answer(s)
B. Venoms
C. Toxins
D. Radiation
F. Some drugs
G. Mechanical injury
Explanation
TYPE I Immediate allergic reactions
COLD temperatures!
3.
Histamine receptors are what type of receptors?
Correct Answer
B. GPCR
Explanation
Histamine receptors are classified as GPCRs (G-protein coupled receptors). GPCRs are a large family of cell surface receptors that are involved in signal transduction. They are characterized by their ability to activate intracellular signaling pathways through the interaction with G-proteins. Histamine receptors, when activated by histamine, initiate a cascade of cellular responses by activating G-proteins and modulating downstream signaling pathways. Therefore, histamine receptors are categorized as GPCRs.
4.
Histamine is found is which of the following location(s)?
Correct Answer(s)
A. Vesicular granules of mast cells or basophils
B. Neuronal tissue in the brain
C. Enterochromaffin-like cells in teh fundus of the stomach
D. Venoms
Explanation
Histamine is found in vesicular granules of mast cells or basophils, neuronal tissue in the brain, enterochromaffin-like cells in the fundus of the stomach, and venoms.
5.
Which of the following is/are not true regarding H1 histamine receptors?
Correct Answer
B. They are Gs coupled
Explanation
They are Gq coupled
6.
Which histamine receptor-has an effect on gastric parietiel cells, cardiac muscle, and some smooth muscle-is Gs coupled-causes an elevation in cAMP
Correct Answer
B. H2
Explanation
The correct answer is H2. Histamine receptor H2 has an effect on gastric parietal cells, cardiac muscle, and some smooth muscle. It is Gs coupled, which means it activates the Gs protein and stimulates the production of cyclic adenosine monophosphate (cAMP), leading to various physiological responses.
7.
Which histamine receptor regulates the release of neurotransmitters in the brain and myenteric plexus?
Correct Answer
C. H3
Explanation
It is Gi coupled to N-type calcium channels
8.
Which histamine receptor is the main receptor that causes a direct decrease in blood pressure?
Correct Answer
A. H1
Explanation
Mainly H1... but some H2 dependency
9.
Edema is mediated by which histamine receptor?
Correct Answer
A. H1
Explanation
Edema is the accumulation of fluid in the tissues, and it is mediated by the H1 histamine receptor. Histamine is a chemical released by the body during an allergic reaction or inflammation. When histamine binds to the H1 receptor, it causes blood vessels to dilate and become more permeable, leading to fluid leakage into the surrounding tissues and resulting in edema. The H1 receptor is primarily responsible for the allergic response, including symptoms such as itching, redness, and swelling.
10.
Which of the followingcardiovascular effects of histamine is/are indicative of histamine release in the skin?
Correct Answer(s)
D. Heat, redness and local swelling
E. Urticaria or hives
Explanation
The cardiovascular effects of histamine that are indicative of histamine release in the skin are heat, redness, and local swelling. These symptoms are commonly associated with an allergic reaction and are caused by the dilation of blood vessels in the skin, leading to increased blood flow and the characteristic redness and swelling. Urticaria or hives, which are also listed as the correct answer, are another common skin manifestation of histamine release and are characterized by itchy, raised welts on the skin.
11.
The axon relfex is the direct action on ______ receptors on sensory nerve endings and/or depolariztion of efferent axons.
Correct Answer
A. H1
Explanation
The correct answer is H1 because the axon reflex involves the direct action on H1 receptors on sensory nerve endings and/or depolarization of efferent axons. This suggests that H1 receptors play a role in initiating the axon reflex response.
12.
Histamine has clinical applications
Correct Answer
B. False
Explanation
Histamine does have clinical applications, particularly in the field of medicine. It is involved in various physiological processes and is used in the diagnosis and treatment of certain medical conditions. Therefore, the statement that histamine has clinical applications is incorrect.
13.
Histamine is a majore player in human asthmas.
Correct Answer
B. False
Explanation
It does NOT play a role, however, asthmatic airways still respond greatly to histamine.
14.
Antagonists of histamine's actions have important clinical uses.
Correct Answer
A. True
Explanation
Antagonists of histamine's actions refer to drugs that block the effects of histamine in the body. Histamine is involved in various physiological processes and can cause allergic reactions, inflammation, and gastric acid secretion. By blocking histamine's actions, these antagonists are commonly used in clinical settings to treat allergies, relieve symptoms of allergic rhinitis, reduce gastric acid secretion in conditions like peptic ulcers, and manage symptoms of histamine-mediated conditions like urticaria. Therefore, the statement that antagonists of histamine's actions have important clinical uses is true.
15.
H2 receptors mediate contraction of intestinal smooth muscle
Correct Answer
B. False
Explanation
H1 receptors mediate contraction of intestinal smooth muscle
H2 receptors mediate parietal cell acid production in gastric mucosa
16.
Which of the following is/are true about physiological antagonists of histamine.
Correct Answer
D. They are inhibitors of degranulation
Explanation
they are vasoconstrictors
They are are bronchodilators
17.
Physiological antagonists bind to the receptor.
Correct Answer
B. False
Explanation
WIKI: Physiological agonism and antagonism is the mechanism of substances to induce the same ultimate effects in the body as other substances, as if they were receptor agonists or antagonists, but without binding to the same receptor.
18.
Antihistamines are physiological antagonists of histamine
Correct Answer
B. False
Explanation
They are histamine receptor antagonists... competitive H1 receptor blockers.
19.
2nd generation antihistamines blcok muscarinic receptors.
Correct Answer
B. False
Explanation
first generation ones do... 2nd mostly do not...
20.
First generation antihistamines possess anti-cholinergic activity.
Correct Answer
A. True
Explanation
First generation antihistamines, such as diphenhydramine and chlorpheniramine, do possess anti-cholinergic activity. This means that they not only block the effects of histamine, but also block the effects of acetylcholine, a neurotransmitter involved in various bodily functions. This can result in side effects such as dry mouth, blurred vision, constipation, and urinary retention. Therefore, the statement that first generation antihistamines possess anti-cholinergic activity is true.
21.
2nd generation drugs have an extended duration of actoin
Correct Answer
A. True
Explanation
Second-generation drugs are a newer class of medications that have been developed to improve upon the limitations of first-generation drugs. One of the key improvements is their extended duration of action. This means that these drugs remain active in the body for a longer period of time, allowing for less frequent dosing and potentially improving patient compliance. Therefore, the statement that second-generation drugs have an extended duration of action is true.
22.
Whcih of the following is/are not second generation antihistamines?
Correct Answer(s)
A. Diphenhydramine
D. Pyrilamine
F. Promethazine
Explanation
Diphenhydramine, pyrilamine, and promethazine are not second-generation antihistamines because they are first-generation antihistamines. First-generation antihistamines are known to cause drowsiness and have a shorter duration of action compared to second-generation antihistamines. Fexofenadine, loratadine, and cetirizine, on the other hand, are second-generation antihistamines that have a longer duration of action and are less likely to cause drowsiness.
23.
Which of the following are major pharmacological effects fo antihistamines?
Correct Answer(s)
A. Sedation
C. Increased heart rate
D. Reversal of histamine-induced vasodilation
Explanation
decreased and thickened secretions
24.
2nd generation antihistamines are more effective than 1st generation ones.
Correct Answer
B. False
Explanation
Equally effective
25.
Antihistamines are an effective treatment in bronchial asthma
Correct Answer
B. False
Explanation
Antihistamines are not considered an effective treatment for bronchial asthma. While antihistamines can help with allergies and symptoms such as sneezing and itching, they do not have a significant impact on the airway inflammation and constriction that occurs in asthma. The mainstay of asthma treatment includes bronchodilators (such as inhalers) and anti-inflammatory medications (such as corticosteroids). Therefore, the statement that antihistamines are an effective treatment in bronchial asthma is false.
26.
Which of the following is/are adverse effects of antihistamines?
Correct Answer(s)
A. Sedation
B. Dry mouth
C. Blurred vision
Explanation
urinary RETENTION
DECREASED GI motility
27.
Antihistamines can have a paradoxical effect on children. (ie. insomnia, nervousness, tremors)
Correct Answer
A. True
Explanation
Antihistamines, despite being commonly used to treat allergies and induce drowsiness, can have the opposite effect on children. This means that instead of causing sleepiness, they may experience insomnia, nervousness, and tremors. Therefore, the statement that antihistamines can have a paradoxical effect on children is true.
28.
Antihistamines are good decongestants
Correct Answer
B. False
Explanation
The statement "antihistamines are good decongestants" is false. Antihistamines are medications that are primarily used to relieve allergy symptoms such as sneezing, itching, and runny nose. They work by blocking the effects of histamine, a substance released by the body during an allergic reaction. While antihistamines can help with some symptoms of congestion, they are not as effective as decongestants in relieving nasal congestion. Decongestants work by narrowing the blood vessels in the nasal passages, reducing swelling and congestion. So, while antihistamines can provide some relief for congestion, they are not considered to be good decongestants.
29.
Which of the following are effective decongestants?
Correct Answer(s)
B. Phenylephrine
C. Pseudoephedrine
D. Oxymetazoline
Explanation
Phenylephrine, pseudoephedrine, and oxymetazoline are all effective decongestants. Decongestants work by constricting blood vessels in the nasal passages, reducing swelling and congestion. Phenylephrine is commonly found in over-the-counter nasal sprays and oral medications. Pseudoephedrine is also available over-the-counter and is often used in combination with other medications to treat congestion. Oxymetazoline is a nasal spray that provides fast relief from nasal congestion. These decongestants are effective in relieving symptoms of nasal congestion caused by allergies, colds, or sinus infections.