Drug Tolerance

In contrast, the BIS is associated with the neurotransmitter Serotonin and brain structures that control memory. Serotonin is regarded by some researchers as a chemical that is responsible for maintaining mood balance, and that a deficit of serotonin leads to depression. The BIS is sensitive to threats of punishment and can be likened to a brake that stops a person from going too far too fast. “The BIS produces anxiety and inhibits ongoing behavior in the presence of novel stimuli, innate fear stimuli, and signals of non-reward or punishment” (O’Brien, Frick 1). The BIS is what we can rely on to tell us when we have had enough for our own

Dosage forms usually are made up of the active compound and other ingredients known as excipients. Excipients can have many functions, they can act as fillers, lubricants, binders, preservatives and antioxidants. A change in the nature of the excipients can significantly affect the stability of the active ingredient as well as its release from the dosage form. Changes in the preparation (the way the compound is made) of the active compound like the use of a different solvent for purification, can affect its bioavailability (The fraction of the dose of a drug that is found in general circulation around the body. It is influenced by such factors such as Absorption, Distribution, Metabolism and Elimination (ADME).

At the same time, the antagonist drugs, ipratropium, attaches to cholinergic receptors and obstruct the attachment of acetylcholine and limit the airways which called bronchoconstriction. Both of these drugs help to breathing easier but in the different

2.Homotropic modulation . 3.Heterotropic modulation. DESENSITIZATION: Desensitization of the postsynaptic neuron is ; the decrease in response to same neurotransmitter stimulus. Means the strength of synaps may be diminished in response as the action potential arrives in repid succession –ie refered as a phenomenon that give rise to so called frequency dependence of synaps . Our nervous system exploy this property for the computational purpose , and can turn this synaps to such means as phosphorylation of proteins involved .

When this takes place, very different changes occur in the nervous system and other target tissue. The hormones involved in this occurrence have a pharmacological effect on the target tissue. Pharmacological effects can be therapeutic, toxic, or lethal. The term “therapeutic effect” describes a situation whereby a drug successfully treats a given condition. Toxicity, on the other hand, results from harmful pharmacological effects.

The dissolving of a drug is highly dependent on the acidity of the solution, in this case our stomach acid. The general rule of thumb is that the pH (1-5) be low in order for the capsule to dissolve quickly. The speed at which the dose dissolved also depend on its form, and can be either tablet, capsule, powder, or etc. If we use a tablet for example, the manufacturer may add starch in order to make the pill swell when water is added which could speed up the process. On the other hand, some processes may require a slower process, or prolong the effect of the drug.

One scientific study researched effect of different nicotine concentration on Oryza sativa and Zea mays. In this research, the quantity of nicotine dose has an opposing effect: increase in nicotine dose inhibited the percentage germination and growth of radicle and plumule for O. sativa, whereas increase in nicotine dose promoted the growth of radicle and plumule, and increased percentage germination for Z. mays for some extent. This suggests that different plants actually react differently to nicotine. Contradicting studies about the effect of nicotine on plant growth have been reported so

The first concept is drug, which can be defined as the “pharmacologic action of the substance itself” (Zinberg 2). In other words, we have to examine the pharmacological effects of the drug on the individual. However, is also important that one considers the form of the drug, route of administration and the dosage when examining a substance. For example, a substance may come in powder or liquid form and could be administrated in a variety of ways, including oral administration, injection, or inhalation. One also has to consider the dose of the drug, or the amount that is necessary for the user to feel its effects.

An increase in the serum corticosterone levels and a long-term reduction of proliferating cells in the hippocampal formation was reported after environmental noise exposure. (Hirano et al. 2006). Noise causes a significant impairment in the early spatial memory, possibly by disrupting glutamate-NMDA receptor signalling and triggering aberrant tau hyperphosphorylation in the hippocampus. In long-term noise-stress, there is oxidative stress, increased cholinergic activity, reduced dendritic count in the hippocampus and elevated plasma corticosterone level, which can cause impaired spatial memory.

They also believe that the two factors that can lead to depresion are the neurologic argument and the genetic argument. We know that the brain functions by sending chemical messages from neurons to neurons using neurotransmitters such as Serotonin ( which release a chemical that helps a person to be calm) and Noradrenaline ( body's initial stress response) . The lack of this chemical messages, according to biological approach, is one of the reasons that lead a person to depression. The cure for the depression, according to the biological approach, is the use of chemical medicines such as Prozac (works by increasing the availability of the mood chemical serotonin) and Effexor (targets serotonin and