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Pineal gland
The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.
![Capsule <p>The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Pin-1-a-ping.png)
Capsule
The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.
![Connective tissue septa <p>The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Pin-1-1-ping.png)
Connective tissue septa
The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.
![Blood vessels <p>The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Pin-1-2-ping.png)
Blood vessels
The conical-shaped pineal gland, or epiphysis cerebri, is attached by the pineal stalk to the roof of the diencephalon of the brain, from which it develops. The gland is surrounded by a capsule of pia mater and arachnoid elements; connective tissue septa penetrate the gland, subdividing it into indistinct lobules. The pineal secretes melatonin, which regulates circadian rhythms. 100x.
![Corpus arenaceum > <p>Corpora arenacea, or brain sand, are commonly found in the pineal gland. These structures consist of accumulations of calcium phosphates and carbonates. Because the pineal is a midline structure, these radio-opaque corpora arenacea are often used as indicators of midline deflection of the brain resulting from pathological conditions.</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Pin-1-3-ping.png)
Corpus arenaceum >
Corpora arenacea, or brain sand, are commonly found in the pineal gland. These structures consist of accumulations of calcium phosphates and carbonates. Because the pineal is a midline structure, these radio-opaque corpora arenacea are often used as indicators of midline deflection of the brain resulting from pathological conditions.
![Pinealocytes > <p>The major cell type of the pineal gland is the pinealocyte, a modified neuron. The main secretory product of pinealocytes is melatonin, which regulates light-dark cycles (circadian rhythms).</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Pin-1-4-ping.png)
Pinealocytes >
The major cell type of the pineal gland is the pinealocyte, a modified neuron. The main secretory product of pinealocytes is melatonin, which regulates light-dark cycles (circadian rhythms).