Veterinary Pharma - General Pharmacology B Flashcards
Which of the following is the main neurotransmitter for the presynaptic nerve terminal of the parasympathetic nervous system?
a.GABA
b.Norepinephrine
c.Epinephrine
d.Acetylcholine
Acetylcholine
The main presynaptic and postsynaptic neurotransmitter for PNS is AcH. Acetylcholine also serves as the main neurotransmitter for the postsynaptic nerve terminals of the SNS
Which of the following processes is not a part of the Phase 1 of biotransformation?
a.Oxidation
b.Acetylation
c. Hydrolysis
d.Reduction
Acetylation
Phase I metabolism includes four major pathways: oxidation, reduction, hydrolysis, and hydration, among which oxidation is the most important. Phase I products act as substrates for Phase II processes, resulting in conjugation with endogenous compounds
Which of the following statements about drug absorption is true?
a. Drugs undergoing first pass metabolism will have increased concentration in the blood
b.Ionized drugs are absorbed much more readily than unionized drugs
c.Basic drugs are absorbed readily in acidic parts of the GI tract
d.Drugs that are highly hydrophilic are poorly absorbed
Drugs that are highly hydrophilic are poorly absorbed
Majority of barriers between body compartments consist of lipid-rich biologic membranes. Lipid solubility governs the rate of diffusion of drugs across said membranes. Ionization reduces a drug’s lipid solubility
Which route of administration will not allow drugs to undergo first-pass metabolism?
a.PO
b.Intraperitoneal
c. Intrarectal
d.Both A and B
Intrarectal
First pass metabolism usually occur in gastrointestinal segments drained by the portal vein. The portal vein
drains blood from the pancreas, the spleen, and the entire GI tract except the caudal rectum and the anal canal
The following are the pharmacologic effects of epinephrine except:
a.Splenic Contraction
b.Increased force of cardiac myocyte contraction
c. Contraction of pilomotor muscles
d.Vasoconstriction at low doses
Vasoconstriction at low doses
Epinephrine produces vasodilation at low doses. At higher doses, it produces vasoconstriction
In which gestating animal species is xylazine contraindicated:
a.Canines
b.Equines
c. Felines
d.Ruminants
Ruminants
When used in gestating cattle especially in the third trimester of pregnancy, xylazine may cause premature parturition
What happens when sweat glands are stimulated through cholinergic receptors?
a.Secretions are increased
b.Secretions are decreased
c.Nothing happens
d.Sweat glands are not stimulated through cholinergic
receptors
Secretions are increased
Sweat glands are mainly under the sympathetic nervous system. The postganglionic neurons of the SNS use acetylcholine as their main neurotransmitter
The following describe the desirable characteristics of a drug to allow it to cross the BBB except:
a.High lipid solubility
b.Small molecular size
c.Unbound to protein
d.The presence of inflammation
The presence of inflammation
Inflammation is not a drug characteristic
This drug is often used with a local anesthetic to restrict its area of action and to prolong its effects
a.Styptics
b.Epinephrine
c.Atropine
d.Dopamine
Epinephrine
Epinephrine acts as a local vasoconstrictor. It also decreases the removal of the drug from the site of administration
Among the following analgesics used in horses, which has the shortest duration of activity?
a.Flunixin Meglumine
b.Phenylbutazone
c. Carprofen
d.Ibuprofen
Phenylbutazone
Flunixin meglumine – 13 hrs
Carprofen – 12 hrs
Phenylbutazone – 8 hrs
Which of the following does not describe isoflurane?
a. Isoflurane has a low blood-gas partition coefficient
b.It is the inhalant anesthetic of choice for patients with increased intracranial pressure
c. It should not be used in swine because it may cause malignant hyperthermia
d.It may be used in animals with liver disease
It should not be used in swine because it may cause malignant hyperthermia
Malignant hyperthermia is a pharmacogenetic myopathy involving a defect of the ryanodine receptor in the sarcoplasmic reticulum. All modern volatile agents including isoflurane, enflurane, sevoflurane, and desflurane can trigger this condition
Drugs that affect the autonomic nervous system produce their effects by doing the following except:
a.Mimic the effect of neurotransmitters
b.Interfere with neurotransmitter release
c.Block the attachment of neurotransmitters to receptors
d.Assist with the uptake of neurotransmitters at the synapse
Assist with the uptake of neurotransmitters at the synapse
Sympatho- and parasympathomimetic drugs are agonists
Which corticosteroid has a rapid onset and is short acting?
a. Dexamethasone
b.Prednisone
c. Flumethasone
d.Triamcinolone
Prednisone
Dexamethasone and triamcinolone are rapid onset intermediate acting drugs. Flumethasone is a slow onset, long acting drug
Which of the following drugs is used to treat organophosphate toxicosis?
a.Propantheline
b.Scopolamine
c.Glycopyrrolate
d.Pralidoxime
Pralidoxime
Pralidoxime is a cholinesterase reactivator. The drug removes and binds the offending phosphoryl group attached to the enzyme, which is then excreted.
Acetylcholinesterase agents prevent the hydrolysis of Ach. Which of the following is the MOA of organophosphates?
a.Acetylation
b.Carbamylation
c.Phosphorylation
d.NOTA
Phosphorylation
They act via phosphorylation. Phosphorylation generally causes irreversible inhibition of acetylcholinesterase
Which of the following anticonvulsant drugs is the best choice to terminate on-going seizures?
a.Phenobarbital
b.Pentobarbital
c. Dichlorofention
d.Cefalexin
Pentobarbital
Pentobarbital acts rapidly. Although phenobarbital is an anticonvulsant, would take around 20-30 minutes to produce an effect even after parenteral administration
The following drug families are non-selective COX inhibitors except:
a.Oxicams
b.Nicotinic acid
c.Acetic acid
d.Coxibs
Coxibs
These are opioid receptors that predominate the cerebral cortex:
a.Mu
b.Kappa
c. Delta
d.Epsilon
Kappa
Mu receptors are located throughout the brain and the lamina I and II of the dorsal horn of the spinal cord. Delta Receptors are found in the limbic system. Kappa Receptors are found in the cerebral cortex and the spinal cord
At the Alpha receptors, which of the following
drugs/neurotransmitters is the most potent?
a.Epinephrine
b.Norepinephrine
c. Dopamine
d.Isoprenaline
Norepinephrine
Norepinephrine binds only to three receptors namely: A1, A2, and B2. Epinephrine on the other hand, binds to four receptors.