The liver has an important role in drug ADME. Which ONE of the following is CORRECT?

Question

BlackTom AI · Accepted Answer

The question asks us to identify which statement about liver roles in drug ADME is correct.
Option 1: 'In phase I biotransformation drugs are converted into more hydrophobic metabolites.' This is misleading. Phase I reactions (e.g., oxidation, reduction, hydrolysis) often introduce or expose polar groups, not increase hydrophobicity; in many cases metabolites become more polar to aid excretion. So this is not accurate.
Option 2: 'Hepatic P450 enzymes mediate drug conjugation.' Cytochrome P450 enzymes primarily carry out oxidative phase I reactions. Conjugation steps (phase II) such as glucuronidation, sulfation, and acetylation are typically mediated by distinct transferase enzymes. Therefore this statement is incorrect.
Option 3: 'The first pass effect is greater if the activity of hepatic biotransformation enzymes is low.' In reality, a higher enzymatic activity in the liver increases the first-pass metabolism, reducing systemic bioavailability after oral dosing. If enzyme activity is low, the first-pass effect would be smaller. Hence this option is incorrect.
Option 4: 'After oral absorption drugs enter the liver via the portal vein.' Correct. After absorption from the gut, orally administered drugs are delivered to the liver through the hepatic portal vein, exposing them to first-pass metabolism before reaching systemic circulation.

In summary, the only statement that aligns with the known anatomy and metabolism of drugs is the fourth option, which correctly describes the route of oral drugs to the liver via the portal circulation, initiating first-pass exposure.

The liver has an important role in drug ADME. Which ONE of the following is CORRECT?单项选择题

类似问题

Cyclophosphamide must be activated by which organ before it can cause crosslinks between DNA strands?

Which of the following statements about metabolism is TRUE:[Fill in the blank]

How does the enzyme CYP3A4 contribute to drug metabolism?[Fill in the blank]

Which of the following statements about metabolism is TRUE:

If a prodrug is converted into its bioactive form through metabolism by a cytochrome P450 enzyme then:

Which is primarily responsible for pharmacologic metabolism?

Where are lidocaine, mepivacaine, and bupivacaine metabolized?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单