Estudo histológico da glândula pineal de Nasua nasua (Quati) empregando microscopia de luz

Abstract

Nasua nasua or coati is a mammal of the carnivorous order and Procyonidae family. They are animals that live in flocks and have a wide geographical distribution throughout South America. The pineal gland is an endocrine gland, whose melatonin synthesis is influenced by the light and dark periods of the day. The objective of this work was to describe the histology of the coati pineal gland, evaluating its arrangement and cellular composition. For this work, 5 pineal glands were used, which were processed according to routine tissue processing techniques and then a paraffin was included. The pineal gland microscopically has a shape similar to a small pine cone and is divided into 3 parts: apex, body and base. The predominant cells in the glandular parenchyma were pinealocytes, which have large, rounded nuclei with little apparent cytoplasm. Externally the coati pineal gland is lined by a connective tissue capsule from which septa depart into the gland. Secretions were observed at the glandular apex.