The Israel Journal of Psychiatry and Related Sciences
Major depressive disorder (MDD) is a heterogeneous, highly prevalent, and moderately heritable disorder. A complex and diverse genetic-environmental interplay converges to set apart a significant minority that is susceptible to MDD, from among those who experience shorter lived and less recurrent intensive and incapacitating forms of sadness.
In traditional folk medicine, Xanthoxylum plants are referred to as 'toothache trees' because their anesthetic or counter-irritant properties render them useful in the treatment of pain. Psychophysical studies have identified hydroxy-alpha-sanshool as the compound most responsible for the unique tingling and buzzing sensations produced by Szechuan peppercorns or other Xanthoxylum preparations. Although it is generally agreed that sanshool elicits its effects by activating somatosensory neurons, the underlying cellular and molecular mechanisms remain a matter of debate.