Beta-3 receptors are coupled with Gs proteins. The most important locations of the receptors are in the bladder
and adipose tissue. Also found in small numbers in the heart and smooth muscle of blood vessels. Stimulation
of the receptor leads to bladder relaxation, increased lipolysis and thermogenesis. (8)
For this experiment adrenergic agonists and antagonists were used. They are sympathomimetic drugs, which
means they cause the effects of the stimulus from the sympathetic nervous system. They have different
specificity and affinity for the receptors mentioned and this results in different responses. Sympatholytic drugs
(antisympathetic) are drugs that inhibit the sympathetic nervous system.(10)
Method:
The software “ Rat Cardiovascular system © J. Dempster, University of Strathclyde (1996-2020) V3.3.7
(30-07.20) ” was utilized in order to perform in-vitro simulations of when injected with different adrenergic
drugs. Stimulation of sympathetic nerves excluding adrenal and “pithed rat” was chosen.
Simulation was started for achieving baseline then the drug was injected, a new experiment for each drug.
Option “symp. nerves (exc. adrenal)” was chosen for administering the stimulation of nerve. Part III: Baseline
was first established by waiting for 1 vertical line, antagonist drug injected first, waited for 1 vertical line,
agonist injected, waited for 1 vertical line. The Window size was then adjusted for optimal reading at the
maximum effect response, screenshots produced in the result part III. Considering this simulation is in a rat we
need to know the normal range, for a healthy adult rat the normal range for heart rate (HR) is 330 - 480 beats
per minute. Heart frequency (HF) baseline from measurements is 7.5. While normal range for arterial blood
pressure (ABP) in a healthy adult rat ranges from 99 -120 mmHg.
Overview simulations (figure number in parentheses)
Part I: Adrenergic antagonist drugs injected Part II: Adrenergic agonists drugs injected
- (1) propranolol 5 mg/kg - (4) norepinephrine 5 μ /kg
- (2) atenolol 5 mg/kg - (5) norepinephrine 10 μ /kg
- (3) phentolamine 5 mg/kg - (6) epinephrine 5 μ /kg
- (7) epinephrine 10 μ /kg
- (8) isoprenaline 5 μ /kg
- (9) isoprenaline 10 μ /kg
- (10) phenylephrine 5 μ /kg
- (11) phenylephrine 10 μ /kg
Part III: antagonist 5mg/kg and then agonist 10 μ /kg Part III: continues
- (12) propranolol 5 mg/kg and epinephrine 10 μ /kg - (18) propranolol 5 mg/kg and isoprenaline 10 μ /kg
- (13) atenolol 5 mg/kg and epinephrine 10 μ /kg - (19) atenolol 5 mg/kg and isoprenaline 10 μ /kg
- (14) phentolamine 5 mg/kg and epinephrine 10 μ /kg - (20) phentolamine 5 mg/kg and isoprenaline 10 μ /kg
- (15) propranolol 5 mg/kg and norepinephrine 10 μ /kg - (21) propranolol 5 mg/kg and phenylephrine 10 μ /kg
- (16) atenolol 5 mg/kg and norepinephrine 10 μ /kg - (22) atenolol 5 mg/kg and phenylephrine 10 μ /kg
- (17) phentolamine 5 mg/kg and norepinephrine 10 μ - (23) phentolamine 5 mg/kg and phenylephrine 10 μ /kg
/kg
2
and adipose tissue. Also found in small numbers in the heart and smooth muscle of blood vessels. Stimulation
of the receptor leads to bladder relaxation, increased lipolysis and thermogenesis. (8)
For this experiment adrenergic agonists and antagonists were used. They are sympathomimetic drugs, which
means they cause the effects of the stimulus from the sympathetic nervous system. They have different
specificity and affinity for the receptors mentioned and this results in different responses. Sympatholytic drugs
(antisympathetic) are drugs that inhibit the sympathetic nervous system.(10)
Method:
The software “ Rat Cardiovascular system © J. Dempster, University of Strathclyde (1996-2020) V3.3.7
(30-07.20) ” was utilized in order to perform in-vitro simulations of when injected with different adrenergic
drugs. Stimulation of sympathetic nerves excluding adrenal and “pithed rat” was chosen.
Simulation was started for achieving baseline then the drug was injected, a new experiment for each drug.
Option “symp. nerves (exc. adrenal)” was chosen for administering the stimulation of nerve. Part III: Baseline
was first established by waiting for 1 vertical line, antagonist drug injected first, waited for 1 vertical line,
agonist injected, waited for 1 vertical line. The Window size was then adjusted for optimal reading at the
maximum effect response, screenshots produced in the result part III. Considering this simulation is in a rat we
need to know the normal range, for a healthy adult rat the normal range for heart rate (HR) is 330 - 480 beats
per minute. Heart frequency (HF) baseline from measurements is 7.5. While normal range for arterial blood
pressure (ABP) in a healthy adult rat ranges from 99 -120 mmHg.
Overview simulations (figure number in parentheses)
Part I: Adrenergic antagonist drugs injected Part II: Adrenergic agonists drugs injected
- (1) propranolol 5 mg/kg - (4) norepinephrine 5 μ /kg
- (2) atenolol 5 mg/kg - (5) norepinephrine 10 μ /kg
- (3) phentolamine 5 mg/kg - (6) epinephrine 5 μ /kg
- (7) epinephrine 10 μ /kg
- (8) isoprenaline 5 μ /kg
- (9) isoprenaline 10 μ /kg
- (10) phenylephrine 5 μ /kg
- (11) phenylephrine 10 μ /kg
Part III: antagonist 5mg/kg and then agonist 10 μ /kg Part III: continues
- (12) propranolol 5 mg/kg and epinephrine 10 μ /kg - (18) propranolol 5 mg/kg and isoprenaline 10 μ /kg
- (13) atenolol 5 mg/kg and epinephrine 10 μ /kg - (19) atenolol 5 mg/kg and isoprenaline 10 μ /kg
- (14) phentolamine 5 mg/kg and epinephrine 10 μ /kg - (20) phentolamine 5 mg/kg and isoprenaline 10 μ /kg
- (15) propranolol 5 mg/kg and norepinephrine 10 μ /kg - (21) propranolol 5 mg/kg and phenylephrine 10 μ /kg
- (16) atenolol 5 mg/kg and norepinephrine 10 μ /kg - (22) atenolol 5 mg/kg and phenylephrine 10 μ /kg
- (17) phentolamine 5 mg/kg and norepinephrine 10 μ - (23) phentolamine 5 mg/kg and phenylephrine 10 μ /kg
/kg
2
