Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Dose Response Curve: Conventional Versus Nonmonotonic01:21

Dose Response Curve: Conventional Versus Nonmonotonic

360
The correlation between a drug's dosage and its impact on a biological system is a cornerstone of pharmacology and toxicology. Conventional dose–response curves, which include graded and quantal relationships, are key to this understanding. Graded dose–response curves depict the spectrum of a biological reaction to different doses within an individual, indicating that as the drug dosage increases, so does the intensity of the response. On the other hand, quantal dose–response...
360
Pharmacokinetic–Pharmacodynamic Relationship: Dose to Pharmacological Effect01:28

Pharmacokinetic–Pharmacodynamic Relationship: Dose to Pharmacological Effect

181
A drug’s dosage and pharmacokinetic properties determine how quickly it acts, how intense its effects are, and how long it lasts. Higher doses increase drug concentration at receptor sites, producing a hyperbolic curve when pharmacologic response is plotted against drug dose. Converting this scale to a log-linear format results in a sigmoidal curve, better representing dose–response relationships.For drugs following a one-compartment model, the pharmacologic response is directly...
181
Dose-Response Relationship: Overview01:03

Dose-Response Relationship: Overview

5.1K
Agonists can bind with and activate receptors, resulting in the formation of drug-receptor complexes. Once formed, these complexes catalyze many biochemical processes at the cellular level and subsequently induce a pharmacologic response. The degree of response is directly proportional to the fraction of activated receptors, which in turn, depends on the concentration of the drug at the receptor site as well as the sensitivity of the receptor. An increase in the administered dose contributes to...
5.1K
Pharmacodynamic Models: Emax Drug–Concentration Effect Model01:18

Pharmacodynamic Models: Emax Drug–Concentration Effect Model

237
The Emax drug-concentration effect model is central to pharmacodynamics in drug discovery and development. This model is predicated on the receptor occupancy theory, which posits that the effect of a drug is directly related to the number of receptors occupied by the drug and the resultant complex formation.The model describes the reversible interaction between a drug (C) and a receptor (R) to form a drug-receptor complex (RC). The kinetics of this interaction are quantified by an equation that...
237
Determination of Multiple Dosing Parameters: Loading and Maintenance Doses01:25

Determination of Multiple Dosing Parameters: Loading and Maintenance Doses

394
A loading dose is an essential pharmacological strategy to rapidly achieve the target plasma drug concentration necessary for an immediate therapeutic effect. This approach is especially critical for drugs characterized by slow absorption or extended half-lives, where delaying therapeutic plasma levels could compromise treatment outcomes. By administering a loading dose, clinicians ensure a prompt onset of drug action, even for agents with complex pharmacokinetic profiles.Achieving steady-state...
394
Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations01:15

Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations

381
Gentamicin, an aminoglycoside antibiotic, is commonly administered via intermittent intravenous infusion to treat severe infections. An intermittent one-hour infusion of gentamicin, administered at eight-hour intervals, allows for precise control of plasma drug concentrations, minimizing toxicity while ensuring therapeutic efficacy. Pharmacokinetic principles govern the dynamics of plasma concentrations and can be mathematically described using specific equations.The plasma drug concentration...
381

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Selection for rapid embryonic development sculpted the new gene Shrew into an accelerator of Drosophila dorsal-ventral axis specification.

Genetics·2026
Same author

Distribution patterns, conservation status and suitable habitat areas of highly valuable medicinal plants in China.

Frontiers in plant science·2025
Same author

Whole-body homogenates restore disrupted microbiota composition in a model insect better than feces or no restoration treatment.

bioRxiv : the preprint server for biology·2025
Same author

Both isoforms of Drosophila ApoLpp (ApoB) cross the blood-brain barrier in adults.

Genetics·2025
Same author

Phylogenomic conflict analyses of plastid and mitochondrial genomes of Impatiens (Balsaminaceae) reveal its complex evolutionary history.

Molecular phylogenetics and evolution·2025
Same author

Past climate cooling and orogenesis of the Hengduan Mountains have influenced the evolution of Impatiens sect. Impatiens (Balsaminaceae) in the Northern Hemisphere.

BMC plant biology·2023

Related Experiment Video

Updated: Apr 25, 2026

High Content Screening Analysis to Evaluate the Toxicological Effects of Harmful and Potentially Harmful Constituents HPHC
11:38

High Content Screening Analysis to Evaluate the Toxicological Effects of Harmful and Potentially Harmful Constituents HPHC

Published on: May 10, 2016

12.4K

Computational tools for fitting the Hill equation to dose-response curves.

Sudhindra R Gadagkar1, Gerald B Call2

  • 1Department of Biomedical Sciences, College of Health Sciences, Midwestern University, Glendale, AZ 85308, USA.

Journal of Pharmacological and Toxicological Methods
|August 27, 2014
PubMed
Summary

Two new free programs, an Excel template and HEPB software, accurately estimate parameters for the 4-parameter nonlinear logistic (Hill) equation. These tools simplify biological response curve analysis, offering objective cut-offs for drug response interpretation.

Keywords:
Computer programDose–response relationshipEC(50)Four-parameter logistic modelHill slopeIterationMethodsPrediction bandSigmoidal curveSimulation

More Related Videos

Expedited Radiation Biodosimetry by Automated Dicentric Chromosome Identification ADCI and Dose Estimation
10:33

Expedited Radiation Biodosimetry by Automated Dicentric Chromosome Identification ADCI and Dose Estimation

Published on: September 4, 2017

19.7K
A Rapid and Quantitative Fluorimetric Method for Protein-Targeting Small Molecule Drug Screening
08:34

A Rapid and Quantitative Fluorimetric Method for Protein-Targeting Small Molecule Drug Screening

Published on: October 16, 2015

9.5K

Related Experiment Videos

Last Updated: Apr 25, 2026

High Content Screening Analysis to Evaluate the Toxicological Effects of Harmful and Potentially Harmful Constituents HPHC
11:38

High Content Screening Analysis to Evaluate the Toxicological Effects of Harmful and Potentially Harmful Constituents HPHC

Published on: May 10, 2016

12.4K
Expedited Radiation Biodosimetry by Automated Dicentric Chromosome Identification ADCI and Dose Estimation
10:33

Expedited Radiation Biodosimetry by Automated Dicentric Chromosome Identification ADCI and Dose Estimation

Published on: September 4, 2017

19.7K
A Rapid and Quantitative Fluorimetric Method for Protein-Targeting Small Molecule Drug Screening
08:34

A Rapid and Quantitative Fluorimetric Method for Protein-Targeting Small Molecule Drug Screening

Published on: October 16, 2015

9.5K

Area of Science:

  • Pharmacology
  • Biostatistics
  • Computational Biology

Background:

  • Biological response curves often follow a sigmoidal shape, well-approximated by the 4-parameter nonlinear logistic (Hill) equation.
  • Estimating Hill equation parameters traditionally requires specialized commercial software or coding expertise.
  • Accessible tools are needed to facilitate the analysis of dose-response data.

Purpose of the Study:

  • To introduce two user-friendly, freely available software programs for fitting the Hill equation to biological response data.
  • To provide researchers with accessible alternatives to commercial software for parameter estimation.
  • To enable objective interpretation of drug response sensitivity.

Main Methods:

  • Developed a Microsoft Excel template utilizing Solver for iterative parameter estimation.
  • Created a stand-alone, graphical user interface (GUI)-based program named HEPB.
  • Both programs estimate EC50 and Hill slope while constraining asymptote parameters; HEPB includes prediction bands and cut-off value calculations.

Main Results:

  • Tested on twelve diverse datasets, yielding parameter estimates consistent with commercial software (GraphPad Prism, R's nls).
  • HEPB calculates prediction bands with user-defined confidence levels and derives EC50 boundary values.
  • HEPB can simulate response values to aid in defining sensitive, normal, and resistant response categories.

Conclusions:

  • The Excel template offers a familiar environment for Hill equation parameter estimation and regression plotting.
  • HEPB provides advanced features including prediction bands, objective response cut-offs, and data simulation.
  • Both developed programs offer reliable and accurate estimation of Hill equation parameters, comparable to established statistical software.