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Chemical details of porphyrin and heme synthesis

The various chemical intermediates are shown in black text with their structural formulae. The responsible enzymes that catalyze each step in the pathway are shown in blue. Enzyme inducers are shown in green and enzyme inhibitors are shown in red. Also shown in red are the diseases and associated symptoms resulting from partial function of two of these enzymes: acute intermittent porphyria resulting from partial function of the PBG-deaminase enzyme, and porphyria cutanea tarda resulting from partial function of the UPG III-decarboxylase enzyme. (Original figure by Clindberg, modified by Ross Boswell. Courtesy of Wikimedia Commons. Creative Commons Attribution-Share Alike 3.0 Unported license.)

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Associated Disorders

  • Acoustic neuroma
  • Acromegaly
  • Acute intermittent porphyria
  • Alzheimer disease
  • Astrocytoma
  • Bell palsy
  • Benign intracranial hypertension (pseudotumor cerebri)
  • Brachial plexopathy, recurrent
  • Breast carcinoma
  • Carpal tunnel syndrome
  • Catamenial epilepsy
  • Catamenial migraine
  • Catamenial sciatica
  • Central sleep apnea
  • Cerebrovascular disorder
  • Chorea gravidarum (gestational chorea)
  • Depression
  • Epilepsy
  • Growth hormone deficiency
  • Hemorrhagic stroke
  • Hereditary coproporphyria
  • Ischemic stroke
  • Kennedy disease (spinal and bulbar muscular atrophy)
  • Meningioma
  • Menstrual epilepsy
  • Menstrual migraine
  • Migraine
  • Multiple sclerosis
  • Myotonic dystrophy
  • Obstructive sleep apnea
  • Oligodendroglioma
  • Parkinson disease
  • Peripheral neuropathy
  • Pituitary adenomas
  • Porphyria
  • Premenstrual syndrome
  • Psychosexual dysfunction
  • Psychosis
  • Recurrent brachial plexopathy
  • Sleep apnea
  • Sleep disorders
  • Stroke
  • Subarachnoid hemorrhage
  • Traumatic brain injury
  • Variegate porphyria
  • Wilson disease