Professor Bledsoe G-protein receptors are the most common targets of psychotropic drugs, and their actions can lead to both therapeutic and side effects. Among the drug design strategies invented, the targeting of G- protein coupled receptors has become of great benefit. The understanding of the different signal transduction pathways, the structures of the receptors involved and the structural design and effect of ligands has proved a major breakthrough in the pharmaceutical practice. The ligand-based approach, quantitative assessment of structure activity relationship and pharmacophore modeling are the main study tools used to come up with these drugs (Stahl, 2013). GPCR dugs act as ligands to the respective receptor to elicit an agonistic, …show more content…
Like those used to manage high blood pressure. An example is Metoprolol. It is a beta-1 selective drug that binds to the beta-1 adrenoceptors to block the adrenergic effect of adrenaline and noradrenaline, which is a G- protein signal transduction pathway (Pharmacotherapy, 2005). The cascade of events that happens leads to reduction in the heart rate and the strength of pumping this in turn reduces the cardiac output and thus the blood pressure. This effect is however, dose-dependent and an overdose could easily result in cardiac collapse. A drug with an extreme agonistic effect would easily cause overexpression of the intrinsic effect of adrenaline which ultimately leads to increased heart rate, profuse sweating, increased breathing rate among other physiological changes. On the other hand, a drug with an extreme antagonistic effect on the beta-1 receptors blocks the activity of adrenaline and noradrenalin on the cardiac muscles resulting in a cascade of events that drastically lower the blood pressure and possibly lead to
Ace Inhibitors are used to treat hypertension and congestive heart failure (CHF). Most of the drugs that are Ace Inhibitors have the common ending –pril. It inhibits an enzyme; that decreases the tension of blood vessels and the blood volume, thus lowering blood pressure. Lotensin (benzapril) comes in tablets and is used for oral administration. It is one of the ace inhibitors that are indicated for treating hypertension. There is warning while using Lotensin when pregnant, it indicates to stop using immediately when pregnancy is detected. Vasotec (enalpril) comes in tablets and injection. It is indicated for the treatment of hypertension and is effective alone or in combination with other Ace Inhibitors agents, especially thiazide-type diuretics. There is a warning for fetal toxicity; when pregnancy is detected; stop using.
...the adrenal glands, attaches to the signal-binding site of a G-protein-linked receptor. When this happens, the G-protein, which has three subunits, is activated. One subunit, the α subunit, of the G-protein detaches, or dissociates, itself from the other two. This subunit carries a GDP molecule which is replaced by a GTP molecule. Then it attaches to a protein called adenylyl cyclase, which converts ATP into cAMP(Adenosine Monophosphate with a cyclic group). Cyclic AMP, the secondary messenger, is released by the adenylyl cyclase and binds to the regulatory portions of the protein kinase, releasing the catalytic portions. Then these catalytic portions are going to undergo the phosphorylation cascade. The newly activated protein kinases transfer their phosphate groups to a protein called phosphorylase which releases glucose from glycogen into the bloodstream.
Craddock, N. N., Jones, L. L., Jones, I. R., Kirov, G. G., Green, E. K., Grozeva, D. D., ... Ferrier, I. N. (2010). Strong genetic evidence for a selective influence of GABAA receptors on a component of the bipolar disorder phenotype. Molecular Psychiatry, 15(2), 146-153.
Not taking the prescribed medication: Medications are prescribed to decrease the workload of the heart, prevent fluid retention and decrease the amount of harmful hormones that are released. When the patient fails to comply with prescribed medications all these things are not managed.
The Role of Dopamine Receptors in Schizophrenia. Retrieved March 3, 2005, From Stanford University, Chemistry department web site, http://www.chem.csustan.edu/chem44x0/SJBR/Mann.htm Naheed, M., & Green, B. (2000). Focus on Clozapine. Retrieved February 7, 2005. From http://www.priory.com/focus14.htm Waddinton, J.L., & Buckley, P.F. (1996).
Drugs: propylthiouracel, methimazole, anesthesia, barbituates, beta blockers, diuretics, lithium, narcotics, phenothiazines, phenytoin (alters binding of T4 to TBG), rifampin, tranquilizers
The second part of this lab was a computer simulation program to illustrate a frog’s electrocardiogram using various drugs in an isolated setting. The computer program entitled “Effects of Drugs on the Frog Heart” allowed experimental conditions to be set for specific drugs. The different drugs used were calcium, digitalis, pilocarpine, atropine, potassium, epinephrine, caffeine, and nicotine. Each of these drugs caused a different electrocardiogram and beats per minute reading. The calcium-magnesium ration affects “the permeability of the cell membrane”(Fox). When calcium is placed directly on the heart it results in three physiological functions. The force of the heart increases while the cardiac rate decreases. It also causes the appearance of “ectopic pacemakers in the ventricles, producing abnormal rhythms” (Fox). Digitalis’ affect on the heart is very similar to that of calcium. It inhibits the sodium-potassium pump activated by ATP that promotes the uptake of extracellular calcium by the heart. This in return strengthens myocardial contraction (Springhouse). Pilocarpine on the other hand
These effect will appear a few hours after usage and disappear in hours or days: Physical effects like, numbness, muscle weakness and trembling, rapid reflexes, increased blood pressure, heart rate, and temperatures, impaired motor skills and coordination, dilated pupils, nausea and sometimes seizers.
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
Mammalian dopamine auto receptors are G-protein coupled receptors (GPCRs) on membranes of neurons. Dopamine receptors are broken into two different groups, D-1 like (D1 and D5) and D2-like (D2, D3, D4). D2-like receptors are found primarily in the midbrain and mediate inhibitory neurotransmission. Increased levels of D2 receptors have been associated with disorders, including both Parkinson’s and ADHD (Anzalone,2012).
... in the action of hallucinogens has provided a focal point for new studies. Is there a prototypic classical hallucinogen? Until we have the answers to such questions, we continue to seek out the complex relationship between humans and psychoactives.
Endocrine Hormones Are Involved In the Homeostasis of Blood Pressure Human body is probably as scientific as it could get with a whole network of controls and balances well in place. We have the nervous systems and immune systems and these systems are there to stay and more importantly they evolve and change with the passage of time. They keep upgrading themselves and this what keeps the man up to par with everything else and the change as and when they do come about. The hormone is like a messenger or a communicator in the case of out body. Once released, it carries the message through and forth and it travels through the main blood stream until it reaches and finds a cell with a receptor that it fits. This has to be a perfect fit and that is why it is sale that it must attach itself to the molecule like a key made for a certain lock. Then, like a key in a lock, the molecule attaches to the receptor and sends a signal inside the cell, which is relayed from here onwards. It is the content of the message which implies as to whether produce, release, take in or reduce the supply of p...
The MATRICS initiative details many animal models of schizophrenia for the purpose of investigating novel compounds with therapeutic efficacy toward the cognitive deficits of schizophrenia. N-methyl-D-aspartate (NMDA) receptor noncompetitive antagonists are appropriate compounds utilized in order to model schizophrenia based on the evidence that pharmacological agents that block the NMDA receptor calcium channel, such as phencyclidine (PCP), ketamine, and MK-801, produce positive and negative symptoms along with cognitive deficits in healthy volunteers, in addi...
For effective treatment of mental health problems it is important to target the underlying biological factors.
Some examples of stimulants include nicotine, cocaine, and amphetamines. These drugs increase our heart rate, respiration, and blood pressure. A person