The negative chronotropic substance is when the substance slows down (decreases also, called a depressants) the heart rate and positive substance speed up (increase also, called stimulant) the rate of the heart. With the effects of the chronotropic substances, these substances can cause an increase in the force and the velocity of the myocardial systolic contraction this is a positive substance, with a negative substance, it can decrease the velocity through the atrioventricular node, also decreasing the degree of activation of sympathetic nervous system (Inc.). Some clinical uses of positive and negative are that the amount of the substance can change the way a person’s heart rate moves, whether it’s with coffee that will increase heart …show more content…
If it is a substance like a sleeping pill, aspirin, or others within this category will decrease the heart rate. Each of these effects has a mechanism of action, to explain; adrenalin also has another name and that is epinephrine. The action that it takes is that it is an alpha and a beta-adrenergic receptor, it reacts by causing the increase in vascular constriction and decreasing vasodilation (Inc.). Also, adrenalin is a hormone that is secreted in the body and involves the fight or flight response, decreasing heart rate, and increasing calcium channels to open. Nodal cells will reach threshold more quickly and will increase the firing rate of the SA node. The faster stimulation of the heart is by the delay in the AV nodes that causes a decrease. Next, is ACh acetylcholine its mechanism of action is that it works on decreasing the activity of adenylate cyclase by acting upon the muscarinic receptors (Callahan). ACh is also a neurotransmitter, which can bind to specific receptors. It is then used by nerve cells to control different things like, the heart, lungs, and muscles. ACh does this by releasing into the SA node, the action that it involves is that it decreases the rate of the SA node, by increasing the potassium and decreasing calcium and sodium movements. Also, Alka seltzers involves in inhibition of cyclooxygenase, aiding in the production of …show more content…
Then the other two lab partners set up the information needed to record the results and the chemicals that were needed at that are needed at a certain time. Also, two of the group members that had gotten the microscopes had received the daphnia magna as well. After receiving the daphnia magna in the pipette, place it on the depression slide. Note: if there is too much liquid on the slide with the daphnia, it will have more room to run around and a person will not be able to receive an adequate reading of the heart rate. So a person will need to remove some of the liquid, leaving just enough so the daphnia does not die. Once this is done place the slide on the microscope staged with a little bit of light, adjust the focus on 4X (lowest objectives) of the microscope so a person can see the heart of the daphnia. The heart is located at the posterior side of the daphnia and is a transparent structure (SLM). Once, the heart is found count the number of beats the heart makes within fifteen seconds of timing it (SLM). After, the fifteen seconds are up multiplying the number of beats (that was counted) by four, and retrieve a chemical substance which will have a letter A-K written on a bottle. When retrieving the substance turn the objectives to make a V and place two drops of the substance beside the daphnia, wait another fifteen seconds and count the heart rate again multiply this number by four
Cardiovascular agents are used to treat the heart, circulatory, and vascular system. Each Sub-Class has a unique active ingredient that targets the issues that our body cannot fight with alone. Patients who have one or more cardiovascular conditions such as CHF, hypertension and an arrhythmia may be taking multiple medications for each condition. There are multiple subclasses that I will be discussing. Even though they all are used for the cardiovascular system, they do target different areas.
The Daphnia magna species in this experiment were kept and preserved in jars of suitable water that acted as small ponds. Each Daphnia Magna was transported individually using a wide-mouthed pipette to a depression slide. The stability of the Daphnia Magna on the slide was attained by using a drop of pond water that acted as a boundary of movement for the Daphnia on the depression slide, small pieces of cotton wool were also used to act as an extra boundary to stop the Daphnia Magna from swimming in circles in the pond drop it was placed in; the stability factor was important in counting the heart beat rate more accurately. The depression slide was then placed under the stereomicroscope, over a cooling chamber that was used to slow down the
In human studies, caffeine and nicotine have been reported to increase the heart rate of human beings (2).
It increases during physical exercise to deliver extra oxygen to the tissues and to take away excess carbon dioxide. As mentioned at rest, the heart beats around 75 beats per minute but during exercise this could exceed to 200 times per minute. The SAN controls the heart rate. The rate increases or decreases when it receives information by two autonomic nerves that link the SAN and the cardiovascular centre in the medulla of the brain. The sympathetic or accelerator nerve speeds up the heart. The synapses at the end of this nerve secretes noradrenaline. A parasympathetic or decelerator nerve, a branch of the vagus nerve slows down the heart and the synapses at the end of this nerve secretes
Sympathetic nervous stimulation: This compensatory mechanism is the first one. Epinephrine (adrenaline) and norepinephrine (noradrenaline) are released which causes an increase in BP and the heart to pump faster and more powerfully. They also increase cardiac output in this way it temporally helps compensate for the hearts reduced ability to pump blood. This is not good long term as it increased the amount of oxygen the myocardium needs.
Reserpine prevents the acceptance mechanism of amines for the storage of granules for sympathetic tissues. Preventing dopamine uptake into granules, allows reserpine to hinder the formation of noradrenaline. In small dosages, reserpine will prevent the release of noradrenaline from separated adrenergic nerve granules.
It’s the big day of the finals and you are experiencing some anxiety. You walk in the classroom and feel like your heart is going to jump out of your chest. This is a normal response to anxiety by the body known as sinus tachycardia. The heart is like a pump and needs to be taken care of for it to work properly. The heart has its own rhythm and on an electrocardiogram (EKG) should have a synchronous pattern called sinus. The normal sinus rhythm should be around 60-100 beats per minute (LeMone, Burke & Bauldoff, 2011). There are many factors that can change the rate and rhythm of the heart. When sleeping your heart rate tends to be slower and should be slower due to the decreased work load on the heart. Something as little as being excited or exercising can cause your heart rate to increase and due to signals to your heart telling it to beat faster to supply the body with more blood and oxygen. The heart can beat over 100 beats per minute at rest, even when supine so it is important to assess for symptoms of any complications (Olhansky & Sullivan, 2013). A normal rhythm, but faster than 100 beats per minute is called sinus tachycardia (LeMone et al., 2011).
Let’s begin with the structure. The structure of Atenolol is as follows: its chemical formula is C14H22N2O3, its relative molecular mass is 266.3g, and its chemical name is (RS)-4-(2-hydroxy-3-isopropylaminopropoxy)phenylacetamide. The physical appearance of the drug itself is a white colored powder that is odorless. The way atenolol, as well as other beta-blockers, work, is that they affect the different beta-recptors located within the human body. Every human has a certain number of beta-receptors located throughout the body, in places such as the heart, lungs, brain, etc. When a person takes a dose of atenolol, it reacts with the beta-receptors to either calm anxiety or treat blood pressure, without altering a person’s actions.
Heart, the key organ of the circulatory system, supplies blood to body parts by rhythmic contraction (systole) and relaxation (diastole) – the heartbeat. Heart rate is the number of beats per minute (BPM) is an important vital signs measurement for cardiovascular health and human’s wellbeing. There are many methods to measure heart rate (or pulse). One simple method is to manually count the pulse by placing finger on Radial pulse (Wrist) or the Carotid pulse (neck). The need for the ceaseless observation of the heart rate motivates for the invention of heart rate monitors. Another essential factor is the Oxygen saturation (So2 or SpO2), the oxygen concentration in hemoglobin. As the name says, we need oxygen to survive. To achieve this, the technique Pulse oximetry is employed. Pulse oximetry produces a graph, called Plethysmogram.
Scopolamine is an alkaloid drug derived from plants in the Solanaceae family. This family of plants are called nightshade plants, and some examples are henbane and jimson weed. The chemical formula of scopolamine is C17H21NO4. Brand names include Scopoderm and Transderm-V. The medication works as an antagonist at muscarinic acetylcholine receptors by blocking the acetylcholine-mediated nerve impulses that travel to the inner ear. The inner ear is where the sense of balance is regulated in humans. Acetylcholine (Ach) is a major transmitter found in the autonomic ganglia that allows neurons to communicate for sensory input and muscle control. Muscarinic receptors are vital in the control of the central nervous system (CNS) and also parasympathetic control of the heart, lungs, and gastrointestinal processes. By blocking the action of these receptors, a result is possible impaired central and peripheral nervous system functioning. Inhibiting this functioning could also cause tachycardia, which can lead to myocardial infarction (heart attack) or angina (chest pain).
There was a series of people used in this experiment to look at blood pressure. The first step was to take the subjects normal blood pressure, then after showing them a scary clip retakes the blood pressure. While taking blood pressure consider age, weight, family history, commitment and gender to see if the subject has low or high blood pressure normally. After receiving all the data the charts that were made were based on age and gender.
For this experiment, you will add the measured amount of the first sample to the measured amount of the second sample into its respectively labeled test tube then observe if a reaction occurs. In your Data Table, record the samples added to each test tube, describe the reaction observed, if any, and whether or not a chemical reaction took place.
Caffeine acts much like stress, increasing heart rate, blood pressure and levels of stress hormones, Caffeine consumption can double your blood levels of the stress hormones cortisol and epinephrine causing
There is also the potential of human error within this experiment for example finding the meniscus is important to get an accurate amount using the graduated pipettes and burettes. There is a possibility that at one point in the experiment a chemical was measured inaccurately affecting the results. To resolve this, the experiment should have been repeated three times.
First we placed the slide under the simple microscope and observed it at ten times magnification level. We each took turns looking. We then copied them as drawings into our Cornell notebooks. After that we changed the magnification to fifty times and observed the slide. We each took turns looking. We then copied what we saw into our Cornell notebooks. After that we changed the magnification level to sixty times and we each took turns looking at the slide. We then copied what we saw into our Cornell notebooks and sat down together. When we were all done drawing we spoke about what we seen and gave each other ideas on how to write our Lab Reports.