St 36 He-sea point, the Earth point on the Earth channel, a strong point to tonify Earth for more Qi and Blood. Sp 6 Crossing point of three foot ying channels. Tonifies yin, of which is included blood. Tonify the kidney, nourish marrow. All points in this section are reinforced.
Du channel enters into the brain.
It is the crossing point of all the Yang channels located at the top of the head, and can attract Qi up towards the head to nourish the marrow. Fills the brain with marrow. This is a local point for Kidney deficiency headache. UB 23 Kidney Shu. Kidney determines the condition of bone and marrow, and the brain is the sea of marrow.