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PharmGKB · ClinPGx

Antipsychotics Pathway (Metabolic Side Effects), Pharmacodynamics

PA166170742 Last updated February 2019 Caroline F. Thorn.
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Drugs & chemicals
2
Genes
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Conditions
31
Reactions
Antipsychotics Pathway (Metabolic Side Effects), Pharmacodynamics pathway diagram
Antipsychotics Pathway (Metabolic Side Effects), Pharmacodynamics — pathway diagram from PharmGKB / ClinPGx
Click to enlarge

About this pathway

Background

Second generation, atypical, antipsychotics such as clozapine, olanzapine, and risperidone, are first line treatment for schizophrenia [Articles:20238348, 19909227]. These antipsychotics are associated with a high likelihood of weight gain [Articles:17291373, 23810019]. Also elevated is risk for metabolic syndrome: a combination of high waist to hip ratio, elevated triglycerides, low HDL, hypertension and insulin resistance [Articles:27441116, 26107755]. Another metabolic side effect for this drug class is elevated prolactin, hyperprolactinemia, which can result in amenorrhea and infertility in women or testosterone deficiency and breast enlargement in men [Article:26872113].

This pathway shows candidate genes involved in the pharmacodynamics of antipsychotics focusing on the metabolic side effects. The relationships depicted show possible connections that are implicated in the process rather than direct interactions.

Neurons of the Arcuate Nucleus

Signals from around the body that regulate food intake and energy metabolism and expenditure include insulin (released from the pancreas), leptin (adipose), ghrelin (stomach) and PYY (distal GI tract) that act on neurons in the arcuate nucleus of the hypothalamus. Depicted are neurons that release the orexigenic Agouti-related peptide (AGRP) and neuropeptide Y (NPY) which stimulate appetite and eating behaviour, and neurons that release anorexigenic peptides proopiomelanocortin (POMC) and cocaine and amphetamine regulated transcript (CARTPT) [Article:15703762]. In the arcuate nucleus of the hypothalamus POMC is cleaved to produce alpha-MSH, in other cell types products include adrenocorticotropin and beta-endorphin and met-enkephalin.

HTR2C and leptin receptors are expressed by distinct subpopulations of arcuate nucleus POMC neurons [Article:21835345]. Both 5-HT and leptin exert their actions in POMC secreting neurons via transient receptor potential C (TRPC) channels that include phospholipase C although the genes that code for these proteins are not established [Article:21835345].

Reactions & interactions (31)

  • Activation
    INS CARTPT
  • Activation
    <i>antipsychotics</i> HTR2C
  • Activation
    NPY NPY1R
  • Activation
    <i>antipsychotics</i> DRD2
  • Activation
    LEPR POMC
  • Activation
    LEP LEPR
  • Activation
    SNAP25 INS
  • Activation
    HTR2C POMC
  • Activation
    <i>antipsychotics</i> NPY1R
  • Activation
    <i>antipsychotics</i> NPY
  • Activation
    GHRL GHSR
  • Activation
    INS POMC
  • Activation
    INS INSIG2
  • Activation
    ANKK1 PRL
  • Activation
    DRD2 ANKK1
  • Activation
    dopamine DRD2
  • Activation
    DRD2 PRL
  • Inhibition
    INS NPY
  • Inhibition
    LEP AGRP
  • Inhibition
    DRD2 POMC
  • Inhibition
    INS AGRP
  • Inhibition
    <i>antipsychotics</i> TH
  • Inhibition
    AGRP MC4R
  • Inhibition
    PYY NPY2R
  • Leads To
    HTR2C Weight gain
  • Leads To
    MC4R Weight gain
  • Leads To
    HTR2C Metabolic Syndrome
  • Leads To
    TH dopamine
  • Leads To
    INSIG2 Weight gain
  • Leads To
    INSIG2 Metabolic Syndrome
  • Leads To
    PRL Hyperprolactinemia

Edit history (2)

  • 2017-10-31 Create
  • 2019-02-20 Update Updated to new illustrator formatting.
Antipsychotics Pathway (Metabolic Side Effects), Pharmacodynamics pathway diagram (enlarged)