Transcript Investigating The Effects Of Caffeine On The 6

Investigating The Effects Of
Caffeine On The 6-Day
Chicken Heart Rate
By: Keila Ortiz ,Kaltrina Sylejmani and Dr. Jacqueline
McLaughlin
The Pennsylvania State University, Berks/Lehigh Valley
College, Fogelsville, PA 18051
Physiology of the Chicken Heart
The chicken heart has 4
chambers
- a right atrium and ventricle
- left atrium and ventricle
Its body temperature is 41-45 ˚C
Pulse Rate of an adult chicken is
as high as 400 beats/min.
Caffeine Background
Caffeine is a trimethylaxanthine
and directly affects the
contractility of the heart and
blood vessels.
Stimulates the central nervous
system.
Stimulant that enhances and
prolongs thermogenesis (heat
creation) .
www.seeleywis.com/mooselips.htm
http:// www.geocities.com
Caffeine Formula
www. chem.purdue.edu/gchelp/molecules/caff.html
Caffeine Molecule
It belongs to a group of chemicals called xanthines
It resembles the molecule adenosine
It is necessary for the construction and maintenance of
DNA.
www.garynull.com/Documents/CaffeineEffects.htm >.
Calcium Blockers and the Electrophysiology of the
Heart
Calcium channel blockers are used to regulate heart beat
and lower the blood pressure.
Calcium blockers are used in the treatment of heart failure
because they reduce peripheral resistance and expand
arteries.
The main kinds of calcium blockers are as following:
diltiazem, nicardipine, nifedipine, verapamil, amlodipine
besylate.
They are used to treat chest pain or to manage hypertension.
Caffeine has shown to increase the intracellular calcium by
promoting its release from the endoplasmic reticulum and by
facilitating its influx through “Slow Channels” in the cell
membrane.
Effects of Caffeine
Affects the neurotransmission in
the central and peripheral
nervous system causing cardiac
arrhythmias
Can increase the heartbeat
Increases the risk of spontaneous
abortion and retardation
It also affects the change in the
electrophysiology of the human
heart
www.hon.ch/HONselect/Selection/
C14.280.067.html
www.garynull.com/Documents/CaffeineEffects.htm
Advantages of Caffeine
Makes people more alert
Less drowsy
Improves coordination
Helps relive headaches
Caffeine consumption
helps the memory and
reduces the incidence of
Parkinson's
disease
www.garynull.com/Documents/CaffeineEffects.htm
Purpose
Different caffeine concentrations, 0.002%,0.02%, and
0.2%, were added to the in vitro chicken heart. It
was hypothesized that the chicken heart rate (BPM)
would respond in such a way that various
arrhythmias would be noted, specially sporatic
episodes of tachycardia and bradycardia due to
increasing concentrations of this drug.
Materials and Methods
Prepared stock solutions of caffeine:
“Window” an egg
-Modified from Cruz, 1993:
a.
b.
c.
d.
Pick up an egg from the incubator.
Place scotch tape on top of the egg .
With the tip of the scissors, puncture the side of the egg
Cut out the part of the egg covered with scotch tape
and use forceps to remove the top shell of the egg.
e. IMMEDIATELY determine the in vivo HR, five times and
record it.
6-day chicken heart
Materials and Methods Continued……
“Explanting” the
embryo
-Modified from Cruz, 1993:
a. Gently position a filter
paper doughnut on top of
the vitelline envelope.
b. Fill a small dish with
saline and place it on the
stage of your dissecting
microscope.
c. Quickly transfer the
explant to the small dish
with warmed saline.
f. Record the in vitro HR
five times.
www.lv.psu.edu/jxm57
Materials and Methods Continued………
Application of Caffeine
a. Using a plastic pipette
apply 0.002% of caffeine in
the in vitro embryo and let it
sit for 30 seconds. After
sitting for 30 seconds
record its HR five times.
b. Using a plastic pipette at all
times, apply 0.02% of
caffeine to the in vitro
embryo, let it sit for 30
seconds and record its
HR five times.
c. Repeat same strategies as
in step a and b but this time
adding 0.2% of caffeine.
6-day chicken embryo
Control
The in vivo and in vitro
HR of the 6-day
Chicken embryo
without exposure to
caffeine.
6-day Chicken Embryo
Data Interpretation
A stereoscopic microscope was used to observe both
in vivo and in vitro 6-day chicken HR’s.
Histograms were constructed to plot data. When
adding different concentrations of caffeine cardiac
arrhythmias were noted such as bradycardia and
tachycardia.
Embryo’s In Vitro HR
140
Heart Rate (BPM)
120
100
Embryo 1
80
Embryo 2
60
Embryo 3
Embryo 4
40
20
0
1
2
3
4
Number of Trials
5
Embryo’s In Vivo HR
160
Heart Rate (BPM)
140
120
Embryo 1
100
Embryo 2
80
Embryo 3
60
Embryo 4
40
20
0
1
2
3
4
Number of Trials
5
0.002% Caffeine Concentration
160
Heart Rate (BPM)
140
120
Embryo 1
100
Embryo 2
80
Embryo 3
60
Embryo 4
40
20
0
1
2
3
4
Number of Trials
5
0.02% Caffeine Concentration
140
Heart Rate (BPM)
120
100
Embryo 1
80
Embryo 2
60
Embryo 3
Embryo 4
40
20
0
1
2
3
4
Number of Trials
5
0.2% Caffeine Concentration
160
Heart Rate (BPM)
140
120
Embryo 1
100
Embryo 2
80
Embryo 3
60
Embryo 4
40
20
0
1
2
3
4
Number of Trials
5
Averages of In Vivo and In vitro HR
Heart Rate (BPM)
Average of In Vivo and In Vitro Heart
Rates
140
120
100
80
60
40
20
0
In Vivo
In Vitro
1
2
3
4
Number of Trials
5
Averages of Different Caffeine Concentrations
Averages of 0.002%, 0.02% and 0.2%
Caffeine concentration
140
120
100
0.002%
80
0.02%
60
0.2%
40
20
0
1
2
3
4
5
Conclusion
Since the in vitro chicken heart experienced
more arrhythmias as the concentrations of
caffeine increased, the proposed hypothesis
was then supported.
Future Experiments
For a future experiment, it
would be interesting to take a
1- day egg, carefully remove a
piece of shell, then using a
syringe apply half a mL of
caffeine (0.2%, 0.02%,
0.002%) to the chorionic
membrane. After 21 days
wherein the chicken is fully
developed, see if the
concentrations applied caused
any abnormalities in the
developed chicken heart.
Any Questions…………?
References
1. Morgan, J.G. and Brown Carter, M.E., Investigating Biology,
Fourth Edition.
San Francisco: Benjamin/Cummings Publishing Co., Inc.
2002.
2. Skinner. B, Braun. N, Caffeine and chick hearts. 2 Aug. 2001.
12 Feb. 2004 <http://www.swartmore.edu>.
3. Caffeine. 5 Mar. 2000. 12 Feb. 2004
<http://www.geocities.com>.
4. Cruz, Y. P. 1993. Laboratory exercises in developmental
biology. Academic Press, San Diego, California, 241 pages.
[ISBN 0-12-198390-0] [Book]
5. Groski, Dawn , and Janet Sinn-Hanlon. Chickscope. 22 Mar.
2004 http://www.chickscope.beckman.uiuc.edu>.
6. Null M.S, Gary, and Bulton Sanford Ph.D. Caffeine: Psychological Effects,
Use & Abuse. 3 Nov. 1981. Orthomolecular Psychiatry. 15 Mar. 2003
<http://www.garynull.com/Documents/CaffeineEffects.htm >.
7. McCain, Dr. Elizabeth E., and Dr. Jacqueline Mclaughlin. Developmental and
Physiological Aspects of the Chicken Embryonic Heart. 18 Mar. 1999. Copyright. 15 Mar.
2004 <http://www.lv.psu.edu/jxm57>.