The activated B cells then migrate through the paracortex to the medulla, where they proliferate as antibody-secreting plasma cells.
In contrast, CD4 single positive (SP) thymocytes migrated directionally toward the medulla, where they accumulated and moved very rapidly.
Epinephrine is produced specifically in the adrenal medulla, where the amino acid tyrosine is transformed through a series of reactions to norepinephrine.
Such signs could theoretically be produced by a lesion located between the midmedulla and the third cervical segment of the spinal cord, but the additional finding of a hypoglossal nerve palsy with atrophy of the tongue accurately localizes the lesion in the midline of the medulla, where the nucleus of this cranial nerve is located.
Some of the daughter cells called T (thymus-derived) cells that are produced in the cortex migrate to the medulla, where they enter the bloodstream through the medullary veins, adding to the lymphocytes seen in the peripheral blood and the lymphoid organs.
Transport efficiency in the TAL is of particular importance in the outer medulla where O(2) availability is limited by low blood flow.
Countercurrent multiplication apparently establishes this gradient in the outer medulla, where there is substantial transepithelial reabsorption of NaCl from the water-impermeable thick ascending limbs of the loops of Henle.
Fibers leave nucleus angularis ventrally and travel to the ventral surface of the medulla where they cross the midline and ascend to the midbrain in pathways resembling the trapezoid body and the lateral lemniscus of mammals.
However, this process does not establish the much steeper osmotic gradient in the inner medulla, where there are no thick ascending limbs of the loops of Henle and the water-impermeable ascending thin limbs lack active transepithelial transport of NaCl or any other solute.
Similarly, few transcripts were shared between two times of day in the non-thyroid tissues; a notable exception was seen in the kidney medulla, where over 60%% of regulated transcripts at 9 00 were also regulated at 12 00, which also constituted half of the regulation observed at 12 00.
