Calyx of Held Calyx of Held The Calyx of Held is a particularly large synapse in the mammalian auditory central nervous system, so named by Hans Held in his 1893 article "Die centrale Gehörleitung" because of its resemblance to the calyx of a flower. Globular bushy cells in the anteroventral cochlear nucleus (AVCN) send axons to the contralateral medial nucleus of the trapezoid body (MNTB), where they synapse via these calyces on MNTB principal cells. These principal cells then project to the ipsilateral lateral superior olive (LSO), where they inhibit postsynaptic neurons and provide a basis for interaural level detection (ILD), required for
Discodermia calyx species, among others with similar toxins, became increasingly studied and important in medicine, particularly relating to chemotherapy. In a later study, scientist concluded that the calyculin A, from "D. calyx," also blocks calcium influx by blocking non-selective ion channels in the cell. Later research looked into "D. calyx" as a species to look at the natural mechanisms that can be used to regulate the toxicity of calyculin A. Scientist found regulation through phosphorylation and dephosphorylation. These among other studies focus on regulation of the toxin as a characteristic of the sponge Discodermia Calyx because of its implications in the fight