[Demonstration of sensor nervous endings in the rat thyroid gland]

The nerve sensitive endings or receptors of the thyroid gland have been studied in twenty adult male rats. Their morphology, their acetyl-cholinesterase specific activity, their mono-amino-oxidase activity and VIP were investigated. Few but constant nerve sensitive endings were observed in the thyroid gland. These receptors were subdivided by their morphology in the next groups: pear-shaped receptors with capsule; capsuled spherical receptors located near vascular walls; ovoidal receptors with capsule and glomerular structure; simple or complex mace-shaped receptors without capsule. The acetyl-cholinesterase technique could just show a unique type or receptor, which corresponds with last one described. The mono-amino-oxidase technique can not show any type of receptors. VIP was not localized immunohistochemically in the sensitive endings of the thyroid gland.