Associated with panic disorder are all except -
Ans is 'd' i.e. GlutamateEtiology of panic disorder Neuroanatomical correlates * It is believed that panic disorder arises from abnormal functioning of the fear network resulting in themaladaptive activation of the fear response which manifests as a panic attack.These fearful experiences may lead to a learned fear memory as demonstrated by avoidant behavior following the onset of PD as well as the feelings of anxiety regarding future episodes.AmygdalaThe amygdala is a key structure of the limbic system with a role in the perception of fear, the fear response and learned fear memory and reduced activity of this region appears to contribute to panic disorder.Periaqueductal GreyThe periaqueductal gray (PAG) is a midbrain structure that has long been shown to be involved in approach and avoidance defense mechanisms.Its role in the pathobiology of panic disorder has been described and may be the locus where panic attacks arise.Upon stimulation, either electrically or through chemical modulators, animal models have exhibited characteristics of a panic response.Anterior cingulated cortexPanic disorder has been associated with a reduction in gray matter volume of the right anterior cingulated cortex.The anterior cingulated cortex has a number of cognitive functions, playing roles in error detection, and emotional modulation.In particular, the rostral dorsal ACC is functionally activated during anticipation of negative interoceptive threat and body sensation such as hyperventilation, a common symptom of a panic attack.CerebellumWhile it is well established that the cerebellum is responsible for balance, the integration of sensory inputs for coordinating fine movements and locomotion, evidence is accumulating that the cerebellum also has a role in cognitive functions such as impulsivity, and may contribute to mental disease.Inhibition of cerebellar nuclei was observed in a model of panic involving deep brain stimulation of the dorsolateral PAG that elicited panic-like symptoms. It was shown that activation of deep cerebellar nuclei was significantly reduced after inducing a panic model of escape with the largest effect being in the vermis and fastigial nucleus.Neurotransmitters and PPIt is believed that dysregulation of various neurotransmitter system in brain regions involving the emotional and physiological correlates of panic and acute anxiety are the basis of panic disorder.Neurotransmitters implicated includeNoradrenaline (especially in the locus coeruleus)Endogenous opioidsSerotoninGABACCKOrexinSerotonergic systemSerotonin has been implicated in panic disorder following research showing that drugs modulating the serotonin system were also able to reduce panic attacks.Serotonin in the brain stem and PAG reduce panic symptoms, but within the amygdale, it works to increase anticipatory anxiety, a critical component of panic disorder.There is an observed reduced functioning of serotonergic receptors within the raphe nuclei in panic patients. Evidence indicates that patient with panic disorder are particularly sensitive to serotonin depletionGABA * Reduced GABAergic inhibitory activity in the PAG and brain regions projecting to the amygdale are believed to play a role in panic disorder...Certain substances can induce panic attack. They are called panicogens. Panicogens can be broadly classified into two groupsPanicogensAct by activating the HPA axis Other specific neurotransmitter systemsCholecystokinin (CCK)YohimbineCuffienceM chlorophenylpiperazineN-methyl- b carboline 3-carboxamide * Carbon-di-oxide * Sodium bicarbonate* Sodium lactateCCK * Cholecystokinin-tetrapeptide (CCK-4) has been established in models of generating panic and genetic studies in CCK system genes, which identified new susceptibility alleles, indicate a role of the this molecule in panic disorder.OrexinRecent findings suggest that the activation of the orexin (or hypocretin) system may be involved in the panic disorder including an increase of orexin in CSF of panic subjects.Orexin is a neurotransmitter deriving mainly from the lateral hypothalamic area and has roles in arousal, and respiration, two characteristic facets of the pathophysiology of panic disorder.
Seratonin
GABA
Cholecystokinin (CCK)
Glutamate
Panic Disorder