Mepyraminse Lab Report

When both NA and Praz act on GPCR in VSM membrane, NA induces production of IP3 and Praz does not. Therefore, to produce same level of contraction from NA only by using NA with Praz, higher concentration of NA is necessary to occupy more receptor. Theoretically, the maximum (100%) concentration should be achieved with high concentration of agonist with antagonist (1 p10). 82.61% of contraction was observed in this experiment. it could be due to tissue damage from experimental process or could be influenced by more than five days storage of prepared tissue (3). 5HT2 receptor is located in the CNS and also located in the periphery (1 p196). The subtypes of 5HT2 are linked to colonic motility (5-HT2A), heart (5-HT2B), and central nervous system (5-HT2c) (1 p196). Meth act as antagonist to 5-HT2A, partial agonist to 5-HT2B, and antagonist to 5-HT2C (1 p199, 4). Both 5HT, and Meth works as agonist, but binding of 5HT to receptor give full response (full agonist), and Meth give less than full response (partial agonist). Meth act as agonist in presence of low concentration of 5HT with Meth. Meth act as antagonist in presence of high concentration of 5HT with Meth. Meth disturbs 5HT binding to receptor to give full response. Therefore, crossover of 5HT only trend line and 5HT with Meth should be observed. Absence of crossover might be due to different efficacies, as Meth is known

The above structure is melittin, which, as discussed earlier, has lytic properties when it encounters several types of membranes. Experiments in selectivity have been done with two different analogues of melittin that were produced, one in which the leucine at position 13 was replaced by alanine, and one in which the 6th and 13th leucine residues were replaced by alanine. The first analog exhibited 10-20% of the hemolytic activity and similar antimicrobial activity when compared to melittin, while the second analog showed 1-2% of the hemolytic activity and similar microbial activity. These results indicate that the leucine zwitter-motif is responsible for the hemolytic, but not the antimicrobial, activity of melittin. (Asthana, p.2)

The enteric nervous system (ENS) is an essential, independent system of monitoring and control regulating nutrient absorption, secretion, motility, blood flow, and sensation in the gastrointestinal (GI) tract (reviewed by Beattie and Smith, 2008; Molderings, 2012). The ENS consists of more than 100 million neurons scattered throughout the gut in clusters called ganglia, which innervate adjacent tissues and organs, including the esophagus, stomach, intestines, pancreas, and gallbladder. At the molecular level, more than 30 transmitters and cotransmitters have been identified, including serotonin. As is the case with the central nervous system (CNS) (reviewed by Gillette, 2006), the main role that serotonin plays in the gut is neuromodulatory (reviewed by Molderings, 2012). In particular, the enteric serotonergic pathways are important for regulating smooth muscle tone, peristalsis, secretion, and sensation (reviewed by Beattie and Smith, 2008).

This study does not provide adequate information on the reversibility of the three toxins presented. There is no data for each of the toxins on the twitch responses-post washing the toxin out of the organ bath. Omitting this data inhibits the ability for this study to reach a conclusion, in terms of finding out on whether there are reversibility qualities of each

Sarpogrelate lacked prominent 5-HT1-like, 5-HT3, beta, H1, H2 and M3 antagonist activity and weakly blocked alpha 1-adrenoceptors (pKB = 6.30). (S)-M-1 showed weak affinity for 5-HT1-like receptors (pKB = 6.30), alpha 1-(pKB = 6.80) and beta- (pKB = 6.54) adrenoceptors, while (R)-M-1 was a weak antagonist at histamine H1 receptors (pKB = 6.49) [2].

Methods: A guinea pig ileum was suspended in an organ bath and superfused with oxygenated, physiological salt solution. The twitch height changes were recorded using LabChart. Cumulative concentration response curves (CRC) were constructed for codeine and morphine using bath concentrations between 10-6 M to 10-4 M and between 10-8 M to 10-5 M, respectively. Naloxone (10-7 M) was added before the experiment and after the first morphine CRC. Tissue desensitisation was performed for morphine (5x10-6 M) while the effects of naloxone (10-7 M) on morphine were observed.

The different groups consisted of MK-801 injections, Saline injections and no injections. The injections were given twice daily for a week long period. The animals were then tested twice daily for a three week long period using 2 methods. The methods consisted of an experimental paradigm and a control paradigm. The experimental paradigm released a pellet that consisted of 45mg dustless precision food pellet every minute for the two hours of testing (120 minutes/2hr = 120 pellets). The control paradigm provided the 120 pellets freely in a dish. Both groups had free and equal access to water throughout the experiment. They had measured which group had consumed more water by weighing the water bottles before and after the

Per Reporter: Both Tia and Mason tested positive for THC via UDS. The meconium test is pending. Tia initially denied using marijuana, but admitted to drug use after being made aware of Mason’s positive UDS. Tia stated that it has been a while since she last use drugs, but was uncertain of how long. Tia received prenatal care; she tested positive for cocaine & THC 5/25/17. No birth defects with the baby. Tia and Mason discharged home 9/14/17. Tia has another son (Jayceon), who lives with his grandmother (Beatrice).

The effects of both agonist (isoprenaline) and antagonists (propranolol) for this receptor were quantified using the schild plot. These receptors are couple to the Gs protein , therefore when the non-selective β agonist binds it activates AC leading to an increase in levels of intracellular cAMP. The elevated cAMP activates protein kinase A and results in phosphorylation of cellular proteins. This causes smooth muscle relaxation and decreases force of contractility. Propranolol however was found to be a competitive antagonist in the rabbit jejunum based on the results of the concentration-response curve as well as schild plot. Propanolol is also non-selective to the subtype it binds to. When cAMP is formed it inhibits myosin light chain kinase which serves to phosphorylate smooth muscle myosin and results in reduced contraction. β₁ adrenoceptors do not appear to have any involvement in the activation of GI contractile activity in the rat jejunum (Akbarali.,

1. Describe the process by which cholera toxin leads to severe fluid and electrolyte loss during diarrhea.

Diphenhydramine (DPH) is a well known first-generation histamine H1-receptor antagonist, commonly used in humans allergic diseases treatments. Its usefulness is principally related with a decrease of histamine effect produced during the hypersensibility reaction. In addition to this effect, DPH has others molecular targets as muscarinic receptors, this fact explains most of its side effects.

Organ Explant Cultures. The researchers used two-day old Wistar rats to obtain an organ explant culture. The head of the Wistar rat was decapitated and the heart was removed and stored in a Hank's Balanced Salt Solution (HBSS) #14025. HBSS is a balanced salt solution that contains calcium, magnesium, sodium bicarbonate and glucose, but contains no phenol red. The purpose of using HBSS is to help maintain pH and osmotic balance and to provide an environment with water and

Measurement of increased cuperuresis after the administration of penicillamine has not shown to be more sensitive than an unenhanced 24-h collection for copper. Others noted that this test

The low amounts of histamine released constantly from mast cells in the gastric mucosa weakly stimulates acid secretion, and so do low levels of gastrin or acetylcholine. Conversely, when low levels of each are present, acid secretion is strongly enforced. Furthermore, pharmacologic antagonists of each of these molecules can block acid secretion. Histamine's effect on the parietal cell is to activate adenylate cyclase, leading to elevation of intracellular cyclic AMP concentrations and activation of protein kinase A. One effect of PKA activation is phosphorylation of cytoskeletal proteins involved in transport of the protein pump from cytoplasm to plasma membrane. The binding of acetylcholine and gastrin both result in an increase of intracellular

Methods: Seventy five healthy albino Wistar rats were divided into 5 groups; the first group received intraperitoneal injection of saline and served as control, 2nd group received a single subcutaneous injection of 30 nmol/g body weights of sodium selenite to induce cataract. 3rd and 4th groups received 0.1 mg/kg of nifedipine and 5.15 µmoles of caffeine respectively, starting two days prior to the administration of selenite and continuing such treatment till the end of experiment. Last group got the combined treatments of nifedipine and caffeine in the same regimen. Animals were decapitated after 5, 15 and 25 days of the experiment.