Elevated Plus Maze Tmaze

The EPM is a rodent model of anxiety that has been used extensively in the characterization of both established drugs and new chemical entities for anxiolytic activity.37 It is an ethologically based test that uses nonpainful, nonaversive stimuli to induce fear and anxiety thus reducing the possible confounds of motivational and perceptual states. The test is a modification of the Y-maze test that relies on the propensity of a rodent to spend less time in the open areas of the maze than the closed areas. A typical apparatus is the shape of a 'plus' sign and has two elevated arms, one open and one closed. The center of the maze is an open area, and the animal is placed on this center area at the start of the test. Over the course of a 5 min period, the time the animal spends in either the open or closed areas is recorded. Since rodents have an innate fear of height and openness untreated/naive animals spend less time on the open versus closed arms, and anxiolytics like diazepam will increase the amount of time spent in the open arm reflecting a decrease in the anxiety of the animal.

The elevated T-maze is a derivation of the EPM and consists of three arms, with one being enclosed by lateral walls. Unlike the EPM where the animal is placed on the open center area at the start of the test, there are two options when running the T-maze test. The animal can be placed in the enclosed arm and since the rodent does not see the open arms until it emerges from the enclosed arm, it can be trained in an inhibitory avoidance response if placed in the enclosed arm multiple times. When placed on the end of the open arms, the animal can move towards the enclosed arm thus performing an escape response. The model has also been pharmacologically validated38 using benzodiazepines (BZs; diazepam), azapirones (buspirone, ipsapirone), and the 5HT2 antagonist, ritanserin. All three drug classes produced anxiolytic effects in the inhibitory avoidance but not the escape component suggesting that the former rather than the latter is related to GAD.

Free Yourself from Panic Attacks

Free Yourself from Panic Attacks

With all the stresses and strains of modern living, panic attacks are become a common problem for many people. Panic attacks occur when the pressure we are living under starts to creep up and overwhelm us. Often it's a result of running on the treadmill of life and forgetting to watch the signs and symptoms of the effects of excessive stress on our bodies. Thankfully panic attacks are very treatable. Often it is just a matter of learning to recognize the symptoms and learn simple but effective techniques that help you release yourself from the crippling effects a panic attack can bring.

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