The document discusses agonists and antagonists, which are molecules that bind to receptors on cells. Agonists such as hormones and neurotransmitters activate receptor functions, while antagonists inhibit receptor functions by blocking binding. The document uses examples of locks and keys to illustrate how agonists and antagonists interact with receptors, with factors like affinity and efficacy affecting their actions. Nursing considerations are discussed for using beta agonist bronchodilators in respiratory conditions.

1. AGONISTS VS
ANTAGONISTS
Alexia Clark – Billi Osman – Katey Gifford – Jackie Perez-Hicks

2. AGONISTS
MOLECULES WHICH BIND TO RECEPTORS ON CELLS
THINK OF LOCK AND KEY; ONLY CERTAIN KEYS WILL
WORK IN CERTAIN LOCKS
HORMONES, NEUROTRANSMITTERS, AND
ENDOGENOUS REGULATORS OF THE BODY
HORMONE: ESTROGEN
NEUROTRANSMITTER: HISTAMINE
ENDOGENOUS REGULATOR: SERATONIN
DRUGS WHICH ACT LIKE REGULATORY MOLECULES
OF THE BODY

3. AGONIST FACTS
REACTIONS MAY NOT PROCEED FASTER DUE TO AN AGONIST BINDING
JUST BECAUSE THE KEY IS IN THE LOCK DOES NOT MEAN THE DOOR WILL OPEN
ANY FASTER
SOME AGONIST ACTION MAY ACTUALLY RESULT IN A SLOWER BODY
FUNCTION
A KEY MAY UNLOCK THE DOOR AND YOU WILL MOVE IN SLOW MOTION

4. BASELINE
LOW BASELINE ACTIVITY MAY BE POSSIBLE IN ANY SYSTEM WITHOUT AN
AGONIST TO REPRESENT THE RECEPTOR/EFFECTOR; BRIEF ACTIVATION IS
POSSIBLE
THERE IS NOT ALWAYS A NEED FOR A KEY TO UNLOCK
SOME DOORS; THEY CAN OPEN WITHOUT
A KEY
THESE DOORS DON’T STAY OPEN VERY
LONG, BUT THEY ARE SUFFICIENT ENOUGH
TO ALLOW OTHERS TO ENTER AND EXIT
(Maybaum 2014)

5. HIGH EFFICACY AGONISTS
LOW CONCENTRATIONS OF A FULL AGONIST MEANS
THAT ONLY SOME AVAILABLE RECEPTORS WILL
ACTUALLY BE OCCUPIED AT ANY GIVEN TIME
WHEN THERE ARE A LOT OF DOORS AND NOT ENOUGH
KEYS AVAILABLE, NOT ALL DOORS WILL BE OPENED
THE EFFECTOR SYSTEM IS ACTIVATED BY EACH EVENT
OF BINDING COMPLETED BY THE AGONIST – “HIGH
EFFICACY“
KEYS REALLY LIKE DOOR LOCKS; THEY WILL ENTER A
LOCK AS OFTEN AS POSSIBLE; A KEY UNLOCKING A
DOOR SIMPLY MEANS THAT THIS DOOR CAN BE
OPENED
(Maybaum 2014)

6. HIGH EFFICACY/CONCENTRATION
ALMOST ALL RECEPTORS MAY BE
OCCUPIED WHEN A FULL AGONIST IS
PRESENT AT A HIGH CONCENTRATION
WHEN A DOOR LOCK HAS A KEY IN IT
ALREADY, YOU CANNOT ADD ANOTHER
KEY; THIS LEAVES MANY UNUSED KEYS
(Maybaum 2014)

7. LOW AFFINITY AGONISTS
EVEN IN HIGH CONCENTRATIONS, A LOW
AFFINITY AGONIST WILL NOT BE ABLE TO BIND
AS EFFICIENTLY TO THE RECEPTOR SYSTEM
SOME KEYS ARE JUST NOT AS GOOD AS
OTHERS, AND YOU CAN HAVE A LOT OF
KEYS THAT DON’T FIT THE LOCKS; LESS
DOORS ARE UNLOCKED WHEN WE HAVE THE
WRONG KEY
THE LOW AFFINITY AGONIST WILL COME OFF
OF THE BINDING SITE MUCH FASTER THAN THE
HIGH AFFINITY AGONIST
WHEN A BAD KEY IS BEING USED, IT WILL BE
EASIER NOT TO USE THAT KEY, BUT RATHER A
GOOD KEY, RESULTING IN AN OPEN DOOR
(Maybaum 2014)

8. ANTAGONISTS
 INHIBITORS OF REGULATORY DRUGS AND MOLECULES; THEY PRODUCE THEIR OWN
EFFECTS BY BLOCKING RECEPTORS
CHILD SAFETY LOCKS ON THE DOORS; THEY WILL NOT ALLOW THE KEY TO ENTER THE
LOCK
RECEPTOR FUNCTION IS LIMITED DUE TO AN AFFINITY, BUT THERE IS LITTLE TO NO
INTRINSIC ACTIVITY WITHIN THE CELL
THESE CHILD SAFETY LOCKS LIKE TO ATTACH THEMSELVES AND DO NOT ASSIST THE KEY
NOT ALL ANTAGONIST ACTIVITY IS BAD; AN AGONIST MAY BE UNABLE TO FULLY BIND
AND GENERATE A RESPONSE, ALLOWING THE ANTAGONIST TO ELIMINATE HARM TO
THE PATIENT
SOME DOORS ARE BETTER OFF CLOSED; IF LEFT OPENED, THERE MAY BE UNWANTED
ENTRY OR EXIT

9. HIGH AFFINITY ANTAGONISTS
EFFECTORS ARE NOT ACTIVATED
ALTHOUGH THE ANTAGONIST BINDS WITH
THE HIGH AFFINITY RECEPTOR
CHILD SAFETY LOCKS ARE REALLY
EFFECTIVE AT KEEPING KEYS FROM
ENTERING A LOCK; SOME UNLOCKED
DOORS MAY NOT EVEN OPEN WHEN A
CHILD SAFETY LOCK IS IN PLACE
(Maybaum 2014)

10. COMPETING AGONISTS &
ANTAGONISTS
THE AGONIST CANNOT FULLY BIND TO
THE RECEPTOR AS IT IS BEING BLOCKED
BY THE ANTAGONIST
SOME CHILD SAFETY LOCKS ARE WEAK
AND KEYS CAN STILL GET TO THE LOCK;
NOT ALL KEYS WILL BE EFFICIENT
ENOUGH TO REACH THE DOOR LOCK
(Maybaum 2014)

11. COMPETING HIGH AGONISTS & ANTAGONISTS
THE ANTAGONIST IS PRESENT HOWEVER THE
AGONIST IS IN HIGH ENOUGH
CONCENTRATION THAT IT CAN COMPETE
FOR BINDING SITES
CHILD SAFETY LOCKS AND KEYS WILL
COMPETE WITH ONE ANOTHER TO SEE WHO
GETS TO THE DOOR FIRST; SOMETIMES THE
KEYS WIN; MORE KEYS = MORE UNLOCKED
DOORS

13. VALUE IN NURSING
• “The value of combination therapy with inhaled corticosteroids and long-acting
b-agonists (ICS/LABA) is well recognized in the management of
asthma and chronic obstructive pulmonary disease (COPD).” (Maple & Roberts,
2014)
• BETA AGONISTS – KEY
• BETA ANDRENERGIC RECEPTORS IN THE SMOOTH MUSCLE OF THE LUNGS – DOOR LOCK
• THE USE OF THE KEY IN THE DOOR LOCK RESULTS IN RELAXATION OF THE SMOOTH MUSCLE IN
THE LUNGS WHICH LEADS TO BRONCHODILATION

14. VALUES IN NURSING
• BETA AGONISTS HAVE A AN AFFINITY FOR BETA 1 RECEPTORS WHICH MAY ALSO
EFFECT MUSCLES IN THE HEART AND SKELETAL MUSCLE
• COMMON SIDE EFFECTS INCLUDE:
• FAST HEART BEAT (TACHYCARDIA) – HEART
• FLUTTERING FEELING IN THE CHEST (PALPITATIONS) – HEART
• SHAKINESS AND CRAMPING OF EXTREMITIES – SKELETAL
• ANXIETY AND NERVOUSNESS – COMBINATION
• APPLICATION IN NURSING
• ASSESS IF BENEFITS OF DRUG USE ARE GREATER THAN SIDE EFFECTS
• TEACH PATIENT PROPER TECHNIQUE OF ADMINISTRATION – I.E. SPACERS
• TEACH PATIENT TO UNDERSTAND HOW OFTEN MEDICATION SHOULD BE TAKEN
• TEACH PATIENT WHAT ALLERGIC REACTIONS TO WATCH FOR

15. REFERENCES
American Thoracic Society. (2014). What are beta agonists? Retrieved from
http://www.thoracic.org/clinical/copd-guidelines/for-patients/what-kind-of-medications-are-
there-for-copd/what-are-beta-agonists.php
Lehne, R. (2012). Pharmacodynamics. Pharmacology for nursing care (8th ed., pp. 51-58). St. Louis,
Mo.: Saunders Elsevier.
Mapel, D., & Roberts, M. (2014). Management of asthma and chronic obstructive pulmonary disease
with combination inhaled corticosteroids and long-acting β-agonists: A review of
comparative effectiveness research drugs, 74(7), 737-755. doi:10.1007/s40265-014-0214-8
Maybaum, J. (n.d.). Pharmacology Principles / Dental IMS-II. Retrieved August 26, 2014, from
http://sitemaker.umich.edu/maybaum.pharmacology.principles/noncompetitive_antagonist