Lecture 5A: Dose Response Flashcards
What is an Agent?
Any chemical, biological, or physical material capable of eliciting a biological response
What is a dose?
the amount of that agent that comes into contact with a living organism or some part of a living organism
What is a response?
The biological reaction to an agent./Change in structure or function, morbidity, or mortality.
What is exposure?
Any condition which provides an opportunity for an external environmental agent to enter the body
Exposure is “____” the body while Dose is “____” the body
Exposure is “outside” the body while Dose is “inside” the body
What is a dose-response relationship?
the relationship between the effect of a substance on a single organism or population in relation to a specific dose.
What is another word for the does-response relationship?
It is also call dose-exposure relationship
Correlative relationship between exposure and the spectrum of effects
refer to as dose–response relationship
Whatever response is selected for measurement, the relationship between the ____________ of the biological system and the __________administered.
degree of response & amount of toxicant
Features of a Dose-Response Graph
- Shows the response data to each experimentally derived dosage
- Shows the dosage or exposure concentration of the chemical of interest.
- Usually in mg/kg (ppm)
- The values are usually in log format
D/R place pharmacology on a mathematical footing while on a practical level they are essential for making estimates of:
- Potency
- Efficacy
Uses of Dose Response (D/R) curves
- Therapeutic ratios of ED50
- Can be used as tool for investigating mechanisms of drug action and structure activity relationships
In a D/R relationship the response is due to
the chemical administered.
the data that is presented in D/R relationship is similarly to the presentation
of “dose response” in pharmacology and toxicology
The dose–response relationship is based on
the knowledge that the effect is a result of a known toxic agent or agents.
In a D/R relationship , the magnitude of the response is
in fact related to the dose.
What 3 other assumptions that recur frequently in D/R relationship?
- There is a molecular target site (or sites) with which the chemical interacts to initiate the response.
- The production of a response and the degree of response are related to the concentration of the agent at the target site.
- The concentration at the site is, in turn, related to the dose administered
The existence D/R relations means there is
A quantifiable method of measuring and a precise means of expressing the toxicity
For any given dose–response relationship, a great variety of
criteria or endpoints of toxicity could be used.