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Schematic diagram of the porphyrin and heme synthesis pathway

Some of the chemical reactions in this pathway occur in the mitochondria (yellow background) whereas others occur in the cytoplasm (white background). The initial reaction and the terminal 2 reactions are performed in the mitochondria. So δ-aminolevulinic acid formed in the mitochondria must move to the cytoplasm, and then, after a series of chemical intermediaries, coproporphyrinogen formed in the cytoplasm must move into the mitochondria to form protoporphyrinogen III and finally heme. (Figure by William Heric. Courtesy of Wikimedia Commons. Creative Commons Attribution-Share Alike 3.0 Unported license.)

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  • Astrocytoma
  • Bell palsy
  • Benign intracranial hypertension (pseudotumor cerebri)
  • Brachial plexopathy, recurrent
  • Breast carcinoma
  • Carpal tunnel syndrome
  • Catamenial epilepsy
  • Catamenial migraine
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  • 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