High levels of intracellular Ca2+, regulated by Cav, increase the levels of Ca-bound calmodulin (CaM), which in turn activates calmodulin-dependent protein kinase II (CaMKII), which is involved in regulating the synthesis and release of proteins and neurotransmitters including brain-derived neurotrophic factor (BDNF), 5-hydroxytryptamine, dopamine, and glutamate, all of which are related to the incidence of PMS. This evidence concerns the gene BDNF and premenstrual tension.