![This is blank.](https://digitalhistology.org/wp-content/themes/histology-unified/imgs/trans.png)
Thyroid gland
Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x
![Parafollicular cells <p>Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Thy-5-1-ping.png)
Parafollicular cells
Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x
![- Secretory granules <p>Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Thy-5-2-ping.png)
- Secretory granules
Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x
![Active follicle cells <p>Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Thy-5-3-ping.png)
Active follicle cells
Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x
![Capillary <p>Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.Endo_.Thy-5-4-ping.png)
Capillary
Parafollicular cells or C cells are located both in the interfollicular connective tissue and within the basal lamina of the follicular epithelium (seen here). These cells are separated from the thyroglobulin by processes from adjacent follicle cells extending over the parafollicular cells. Parafollicular cells have a pale cytoplasm with secretory granules containing calcitonin. Calcitonin secretion lowers, and is regulated by, blood calcium levels. 1000x