Dissection and Coronal Slice Preparation of Developing Mouse Pituitary Gland

We present a protocol to dissect pituitary glands and prepare pituitary coronal sections from developing mice.

The pituitary gland or hypophysis is an important endocrine organ secreting hormones essential for homeostasis. It consists of two glands with separate embryonic origins and functions — the neurohypophysis and the adenohypophysis. The developing mouse pituitary gland is tiny and delicate with an elongated oval shape. A coronal section is preferred to display both the adenohypophysis and neurohypophysis in a single slice of the mouse pituitary.

The goal of this protocol is to achieve proper pituitary coronal sections with well-preserved tissue architectures from developing mice. In this protocol, we describe in detail how to dissect and process pituitary glands properly from developing mice. First, mice are fixed by transcardial perfusion of formaldehyde prior to dissection. Then three different dissecting techniques are applied to obtain intact pituitary glands depending on the age of mice. For fetal mice aged embryonic days (E) 17.5 - 18.5 and neonates up to 4 days, the entire sella regions including the sphenoid bone, gland, and trigeminal nerves are dissected. For pups aged postnatal days (P) 5 - 14, the pituitary glands connected with trigeminal nerves are dissected as a whole. For mice over 3 weeks old, the pituitary glands are carefully dissected free from the surrounding tissues. We also display how to embed the pituitary glands in a proper orientation by using the surrounding tissues as landmarks to obtain satisfying coronal sections. These methods are useful in analyzing histological and developmental features of pituitary glands in developing mice.

The pituitary gland or hypophysis is an important endocrine organ secreting hormones essential for homeostasis^1,2. Anatomically, the pituitary gland is a ''two-in-one'' structure consisting of the neurohypophysis and the adenohypophysis. These parts have different embryonic origins and function very differently. The neurohypophysis is derived from the neural ectoderm and secretes oxytocin and antidiuretic hormone. The adenohypophysis originates from Rathke's pouch and is responsible for the release of hormones including growth hormone, prolactin, thyroid-stimulating hormone, follicle-stimul....

C57BL/6 mice are bred in specific pathogen-free conditions. All animal experimental methods are in compliance with the guidelines approved by the Animal Care and Ethics Committee at Second Military Medical University.

1. Dissection of Postnatal Developing Pituitary Gland

1. Perform anesthesia: Place neonatal mice (P0 - P5) on crushed ice to induce hypothermia. For mice older than 5 days of age, inject 5% urethane (30 µL/g of body weight) intraperitoneally to induce anesthesia. As.......

This protocol presents a method to dissect pituitary glands from developing mice. For the neonatal mouse, the whole sella regions containing the pituitary gland, the trigeminal nerves, and the underneath sphenoid bone were dissected out from the skull base. The tiny and delicate pituitary gland remained intact during the process (Figure 1A). For mice older than 5 days, the pituitary glands attached to the lateral trigeminal nerves were then isolated. The gros.......

For developing murine pituitaries, it has been technically difficult to obtain proper coronal sections due to their tiny and fragile features and unique anatomical characteristics^6,8. Some research groups thus chose mid-sagittal sections to analyze the morphology of embryonic and neonatal pituitary^11,12. Though the mid-sagittal section of pituitary is also capable of showing anterior, intermediate, and po.......

This work was supported by the grants from National Natural Science Foundation of China (31201086, 31470759 and 31671219) and Shanghai Natural Science Foundation (12ZR1436900).