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Pre-locus coeruleus is a small nucleus in the brainstem. This small cluster of neurons also is referred to by the abbreviation "pre-LC". It was named "pre-LC" because it lies just rostral to (in front of) the locus coeruleus, which is commonly abbreviated "LC". ==Definition== The pre-locus coeruleus was first formally defined during the course of neuroanatomical tract-tracing and c-Fos experiments aimed at uncovering the connections and functions of aldosterone-sensitive HSD2 neurons in the nucleus of the solitary tract. First, HSD2 neurons were found to innervate the pre-LC, as evidenced by (1) dense labeling with an anterograde axonal tracer in pre-LC after that tracer had been injected into the nucleus of the solitary tract and (2) the complementary finding of retrograde labeling of HSD2 neurons after injection of a retrograde tracer into the pre-LC.〔 Further, experimental conditions which activate the HSD2 neurons simultaneously activate a cluster of neurons in pre-LC, in the same location as axon terminals labeled with an anterograde tracer from the NTS.〔 Based on these observations, the pre-locus coeruleus ("pre-LC") was defined as the cluster of neurons which: (1) are found in a specific location rostral to the LC (see "Location," below), (2) receive axonal input from HSD2 neurons in the NTS, and (3) become c-Fos positive during dietary sodium deprivation. These features consistently and reliably identify a very specific subset of neurons in the dorsolateral pons, named the pre-locus coeruleus, or "pre-LC." Some investigators have used other terms including "precoeruleus," "peri5Me," and "pericoeruleus" to refer less specifically to regions of the brainstem anterior to the LC, but the term pre-LC very specifically refers to the group of neurons as defined above. Subsequently, it was discovered that every c-Fos-positive neuron in the pre-LC (after sodium deprivation) also expresses the transcription factor FOXP2.〔 Given that sodium deprivation is a time-consuming experimental manipulation, and that FoxP2 is stably expressed without any experimental manipulation, this transcription factor can serve as a useful surrogate marker for labeling pre-LC neurons. However, it should be noted that FoxP2 expression is found in several nearby brain regions (not including the locus coeruleus, mesencephalic nucleus of the trigeminal, or laterodorsal tegmental nucleus), so it is not unique to the pre-LC. That is, every pre-LC neuron expresses FoxP2, but not every neuron that expresses FoxP2 is part of the pre-LC. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pre-locus coeruleus」の詳細全文を読む スポンサード リンク
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