300
Experimental evidence and radioligand analyses have defined the presence at this level of three different types of serotonin receptors [ 10 , 28 , 85 , 136 , 137 ] , i . e . 5 - HT1A , 5 - HT2A / 2C and 5 - HT7 [ 98 ] , one linked to a stimulation of inositol phosphates ( 5 - HT2 subtype ) , while the others two are linked to cAMP activity .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Anatomy 
Text: {0} 
Answer:
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