Related Experiment Video

Updated: Aug 12, 2026

In vivo Liver Endocytosis Followed by Purification of Liver Cells by Liver Perfusion
12:35

In vivo Liver Endocytosis Followed by Purification of Liver Cells by Liver Perfusion

Published on: November 10, 2011

Development of the hepatic mixed-function oxidase system and its metabolism of warfarin in the perinatal rat

M G MacDonald, M J Fasco, L S Kaminsky

    Developmental Pharmacology and Therapeutics
    |January 1, 1981
    PubMed

    Insights

    The rat hepatic microsomal mixed-function oxidase system develops significantly before birth and rapidly after birth. Key components like cytochrome P-450 and reductase show distinct developmental patterns, with specific isozymes emerging during maturation.

    Area of Science:

    • Pharmacology
    • Biochemistry
    • Developmental Biology

    Background:

    • The hepatic microsomal mixed-function oxidase system is crucial for drug and xenobiotic metabolism.
    • Understanding its developmental trajectory in rats is essential for pharmacokinetic studies.

    Purpose of the Study:

    • To investigate the developmental changes in the rat hepatic microsomal mixed-function oxidase system.
    • To analyze the ontogeny of cytochrome P-450, cytochrome b5, and NADPH-cytochrome c reductase.

    Main Methods:

    • Analysis of cytochrome P-450 and b5 concentrations.
    • Assay of NADPH-cytochrome c reductase and R-warfarin hydroxylase activities.
    • Determination of these components across various postconceptional ages (18-54 days).

    Main Results:

    • Cytochromes and reductase were present prenatally, increasing with age.
    • Significant increases in these components were observed in the first two days post-birth.
    • Cytochrome P-450 levels rose markedly at puberty, while reductase activity matured earlier.

    Conclusions:

    • The rat hepatic microsomal system exhibits distinct developmental stages.
    • Cytochrome P-450 UT-C becomes predominant by 37 days postconception and increases with age.
    • These findings provide insights into the maturation of drug-metabolizing enzymes in developing rats.

    More Related Videos

    Generation of a Rat Model of Acute Liver Failure by Combining 70% Partial Hepatectomy and Acetaminophen09:44

    Generation of a Rat Model of Acute Liver Failure by Combining 70% Partial Hepatectomy and Acetaminophen

    Published on: November 27, 2019

    Measurement of Fatty Acid β-Oxidation in a Suspension of Freshly Isolated Mouse Hepatocytes11:03

    Measurement of Fatty Acid β-Oxidation in a Suspension of Freshly Isolated Mouse Hepatocytes

    Published on: September 9, 2021

    Related Concept Videos

    Drug Metabolism: Phase I Reactions01:17

    Drug Metabolism: Phase I Reactions

    A phase I reaction is a biochemical process that introduces a functionally reactive polar group to a substance. This transformation predominantly occurs in the liver, facilitated by the cytochrome P450 system of hemoproteins situated in the lipophilic endoplasmic reticulum of cells. The metabolite generated through this process can have varying polarities. If it is sufficiently polar, it can be easily excreted in the urine due to its water compatibility. However, if the metabolite is nonpolar,...
    Drug Metabolism: Phase II Reactions01:14

    Drug Metabolism: Phase II Reactions

    Phase II reactions are essential for the detoxification and elimination of drugs from the body. These reactions involve the conjugation of parent drugs or their phase I metabolites with endogenous molecules, resulting in more hydrophilic drug conjugates. The primary conjugation reactions in this phase are sulfation and glucuronidation. Both sulfation and glucuronidation typically produce biologically inactive metabolites. However, in some cases involving prodrugs, active metabolites may be...
    Pharmacokinetics in Pediatric Patients: Drug Metabolism01:24

    Pharmacokinetics in Pediatric Patients: Drug Metabolism

    In pediatric care, understanding the nuances of hepatic drug metabolism is crucial, as it significantly differs from that of adults. This divergence is primarily due to the developmental stage of drug-metabolizing enzymes, which affects how medications are processed in the body. In neonates, for instance, the activity of Phase I enzymes—critical for the initial breakdown of drugs—is markedly reduced, functioning at just 20–40% of the levels seen in adults. This reduction poses a challenge in...
    Effect of Hepatic Disease on Pharmacokinetics: Drug Dosing and Hepatic Blood Flow01:26

    Effect of Hepatic Disease on Pharmacokinetics: Drug Dosing and Hepatic Blood Flow

    Chronic liver disease significantly impacts drug metabolism due to alterations in hepatic blood flow and enzyme accessibility. This disruption affects the body's pharmacokinetics—the movement and processing of drugs within the system. Key enzymes crucial for metabolizing medications become less accessible, changing how drugs are processed and utilized. Furthermore, liver disease influences the synthesis of plasma proteins, such as albumin and globulins, which play critical roles in drug binding...
    Effect of Hepatic Disease on Pharmacokinetics: Active Drug, Metabolite and Fraction of Metabolized Drug01:14

    Effect of Hepatic Disease on Pharmacokinetics: Active Drug, Metabolite and Fraction of Metabolized Drug

    In pharmacotherapy, monitoring drug concentrations is paramount, especially for drugs whose therapeutic effects hinge on both the active compound and its metabolite. Hepatic impairment profoundly influences drug potency by altering liver function. If the drug is more potent than its metabolite, impaired liver function amplifies drug activity due to elevated drug concentration levels. Conversely, if the metabolite holds greater potency, diminished liver function diminishes drug activity by...
    Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test01:22

    Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test

    In clinical practice, the direct measurement of hepatic blood flow to evaluate liver function presents significant challenges due to the intricate and specialized nature of the necessary techniques. Consequently, healthcare professionals often rely on empirical estimates derived from thorough patient examinations and liver function tests to gauge liver health. Among the tools at their disposal, the Child–Pugh and MELD scoring systems stand out for their ability to categorize and assess the...