The development of blood and lymph vessels of human parathyroid glands in embryonal, fetal and postnatal period.

The aim of the article is to investigate the development of blood and lymph systems in human parathyroid glands in prenatal and postnatal periods. The first capillaries are observed in these glands already in the lunar month 2. At the middle of pregnancy blood supply is increased, being extremely abundant in lunar months 9 and 10, as well as during the first year of life. As parts of the lymph system, intercellular lymph spaces are noticed in the parathyroid glands already in the lunar month 2, and also later, when lymph vessels are situated along the gland or in its connective capsule and within the gland parenchyma respectively. All these findings could be connected with the early function of these glands, as well as with the possibility that parathyroid hormone (PTH) is not transferred by blood only but by lymph as well.