Download Do you know about blood pressure (BP)

Effects of drugs on Rabbit
blood pressure
Pharmacological Department
Z.G.Song
Questions:
1. Do you know about blood pressure (BP) ?
BP is the product output and peripheral vascular
resistance. It can be decreased and increased by
actions of drugs on either the peripheral
resistance of the cardiac output, or both.
2. Do you know about the normal BP?
normal BP is defined as a diastolic BP
between 80-90 mmHg (mercury) and systolic
BP between 120-130 mmHg.
Abnormal BP include: hypertension (High BP) and
hypotension (Lower BP)
Hypertension: diastolic BP is greater than 90 mmHg
and/or systolic BP is greater than 140 mmHg.
Hypotension: diastolic BP is lower than 60 mmHg and/or
systolic BP is lower than 90 mmHg.
Hypertension:
Elevated blood pressure is an extremely common disorder, affecting
approximately 20% of the population. Although many of these
individuals have no symptoms:
1. Persistent throbbing Headaches
2. Blurred vision
3. Nausea and vomiting
4. Ringing in your ears
5. Right side chest pain
6. Swollen feet
chronic hypertension-either systolic or diastolic can lead to heart
failure, myocardial infarction, renal damage, and cerebrovascular
accidents. The incidence of morbidity and mortality significantly
decreases when hypertension is diagnosed early and is properly
treated.
3. How to do if someone have high BP?
Six Ways to Lower Blood Pressure
4. Hypotension:
Hypotension is caused by some
reason, e.g. drugs and cardiac.
Most severe consequence is shock .
（One）Experimental
drugs:
1. 0.01% Noradrenaline.
2. 0.01% Adrenaline Hydrochloride.
3. 0.1% Isoproterenol Sulfate.
4. 1% Phentolamine.
5. 0.01% Propranolol Hydrochloride.
6. 1% Heparin.
6. 5% Sodium Citrate.
7. 20% Urethane.
Let us recall the drugs (effects on BP):
1. a, β-receptor agonist
Adrenaline (a 1, a 2,β 1, β2),
2. a, -receptor agonist
Noradrenaline (a 1, a 2) can activate
β 1 -receptor
3.β -receptor agonist
Isoproterenol (β 1, β2).
4. Phentolamine:
a-receptor antagonist (a 1, a 2)
Adrenaline reversal:
The vasoconstrictive action of adrenaline is
interrupted,but vasodilation of othervascular
beds caused by stimulation of β–receptors is not
blocked.
5. Propranolol
β -receptor antagonist
（Two）
Objectives ?
1. To learn method of recording blood
pressure via carotid artery cannula.
2. To observe effects and analyze interactions
of adrenaline, noradrenaline, isoproterenol,
propranolol, phentolamine on the rabbit
blood pressure.
（Two）Experimental
drugs:
5. 2N Hydrochloric Acid
6. 30mg% Sodium Sulfadiazine
7. 1% Heparine
8. 20% Urethane
（Three） Experimental animal
domestic rabbit , 2.5～3.0kg.
（Four） Experimental
equipments:
1. Rabbit operating table
2. Mammal surgical instruments
（Four） Experimental
equipments:
3. Arterial cannula, Blood pressure
transducer, RM6240 signal acquisition and
processing system.
（Five） Steps and methods
1. Debuggment and connection of device:
. Connect the head of blood pressure transducer with a
three-way, one opening of three-way connecting arterial
cannula. Rotate rotary handle of three-way to make the
cavity of transducer link with air through arterial
cannula. Sodium citrate is slowly injected into
transducer and artery cannula by syringe through
another opening of three-way, clear the air in transducer
and artery cannula, then rotate rotary handle, and close
three-way. connect blood pressure transducer with the
RM6240 signal acquisition and processing system.
Operate the computer and enter blood pressure
recording interface in RM6240 signal acquisition and
processing system, adjust baseline, sensitivity and paperspeed.
（Five） Steps and methods
2. Take a rabbit, weighten, anesthetized with
20% urethane (5ml/kg) by intravenous
injection.
When do we begin to operate?
paying attention to:
1. muscle tension degrade
2. respiratory rate from fast to slow
3. corneal reflex disappear
（Five） Steps and methods
3. Fixing rabbit and operation:
the rabbit was fixed to the operating table
on the back and the neck should be fixed
straightly. Shearing hair in the neck, a
incision should be cut about 5-7 cm long
with a scalpel, and subcutaneous tissue
and muscle should be separated bluntly
to find out trachea，then carotid sheath in
which there were carotid artery, vagus
nerve, decompression nerve and
sympathetic nerve could be found on
both sides under the trachea.
4.Arterial intubation
the right carotid artery was separated about 3cm
long, two reserve threads should be made across
the artery. Then 1% heparin was injected by
intravenous injection which dose was 1ml/kg.
Finally, the artery proximal heart is clamped with
artery occlusion, and the artery distal heart is
ligated. Then at the proximal of ligation a bevel
should be cut, arterial cannula should be insert in
the direction of towards heart, and arterial
cannula should be enclosed tightly with thread to
avoid slippage.
5. Depiction of normal blood pressure curve:
6. Observe and analyze effects of drugs
on blood pressure:
Nor(0.5ml/kg)–Adr( 0.5ml/kg)– Phe
(0.5ml/kg)– Adr (0.5ml/kg)–Iso
(0.5ml/kg)–Prop (0.5ml/kg)–Iso (0.5ml/kg)
※ Pay attention to:
1. After every administration, wash remain
drug in the head of syringe with a small
amount of saline (0.3ml) quickly.
2. The next drug should be administered after
the disappearance of action on drugs .