Endocrine System

Pituitary Gland, Rathke's Cleft - Dilation

Narrative
Comment:
Dilated persistent Rathke’s clefts are relatively common in rats and typically contain eosinophilic colloid-like proteinaceous material. Cholesterol clefts (arrow, Figure 1 and Figure 2), as well as free erythrocytes (Figure 3), may be present. Pituitary cysts may also be present (see Pituitary Gland - Cyst ).
Recommendations:
Since chronic studies may incorporate in utero exposure, developmental alterations potentially related to treatment could influence the ultimate presence and appearance of Rathke’s cleft. Thus, this change should be documented when present. A severity grade is appropriate if there is a potential treatment-related effect on the occurrence or severity of this change. Hemorrhage or cholesterol clefts within the dilated Rathke’s cleft should not be diagnosed separately unless warranted by severity.
Related Links:
Pituitary Gland - Cyst
References:

Capen CC. 1983. Functional and pathologic interrelationships of the pituitary gland and hypothalamus. In: Endocrine System (Jones TC, Mohr U, Hunt RD, eds). Springer, New York, 103-120.

Abstract: http://www.springer.com/medicine/pathology/book/978-3-642-96722-1

Capen CC, DeLellis RA, Yarrington JT. 1991. Endocrine system. In: Handbook of Toxicologic Pathology (Haschek WM, Rousseaux CG, eds). Academic Press, New York, 697-705.

Abstract: http://www.sciencedirect.com/science/book/9780123302151

Carlton WW, Gries CL. 1983. Cysts, pituitary; rat, mouse, and hamster. In: Endocrine System (Jones TC, Mohr U, Hunt RD, eds). Springer, New York, 161-163.

Abstract: http://www.springer.com/medicine/pathology/book/978-3-642-96722-1

Gon G, Nakamura F, Ishikawa H. 1987. Cystlike structures derived from the marginal cells of Rathke's cleft in rat pituitary grafts. Cell Tissue Res 250:29-33.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/3652164

Herrick E, McCormack S. 1952. The occurrence and nature of cysts in the pituitary of fowls and rats. Trans Kans Acad Sci 55:178-183.

Abstract: http://www.jstor.org/stable/3625875

Iwata H, Hosoi M, Miyajima R, Yamamoto S, Mikami S, Yamakawa S, Enomoto M, Imazawa T, Mitsumori K. 2000. Morphogenesis of craniopharyngeal derivatives in the neurohypophysis of Fisher 344 rats: Abnormally developed epithelial tissues including parotid glands derived from the stomatodeum. Toxicol Pathol 28:568-574.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/10930044

Kouki T, Imai H, Aoto K, Eto K, Shioda S, Kawamura K, Kikuyama S. 2001. Developmental origin of the rat adenohypophysis prior to the formation of Rathke's pouch. Development 128:959-963.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/11222149

Lansdown AB, Grasso P 1971. Histological observations on a Rathke's cleft abnormality in a laboratory rat. J Comp Pathol 81:141-144.

Abstract: http://www.sciencedirect.com/science/article/pii/0021997571900661

MacKenzie WF, Boorman GA. 1991. Pituitary gland. In: Pathology of the Fischer Rat: Reference and Atlas (Boorman G, Eustis S, Elwell M, Montgomery CA, MacKenzie W, eds). Academic Press, San Diego, 485-500.

Abstract: http://www.ncbi.nlm.nih.gov/nlmcatalog/9002563

Morton D, Tekeli S. 1997. "Have you seen this?" Pituitary cysts in a mouse. Toxicol Pathol 25:333.

Full Text: http://tpx.sagepub.com/content/25/3/333.long

Quintanar-Stephano A, Munoz Fernandez L, Quintanar JL, Kovacs K. 2001. Cysts in the rat adenohypophysis: Incidence and histology. Endocr Pathol 12:63-71.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/11478270
  • Image of Rathke's cleft dilation in the pituitary gland from a female F344/N rat in a chronic study
    Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. The dilated Rathke's cleft is filled with intensely eosinophilic proteinaceous material with cholesterol clefts (arrow) present at the edge of the dilated cleft.
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Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. The dilated Rathke's cleft is filled with intensely eosinophilic proteinaceous material with cholesterol clefts (arrow) present at the edge of the dilated cleft.
Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. The dilated Rathke's cleft is filled with intensely eosinophilic proteinaceous material with cholesterol clefts (arrow) present at the edge of the dilated cleft.
Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. Higher magnification of Figure 1 shows the dilated Rathke's cleft filled with intensely eosinophilic proteinaceous material and the cholesterol clefts (arrow) at the edge of the dilated cleft in greater detail.
Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. Higher magnification of Figure 1 shows the dilated Rathke's cleft filled with intensely eosinophilic proteinaceous material and the cholesterol clefts (arrow) at the edge of the dilated cleft in greater detail.
Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. The dilated Rathke's cleft contains pale eosinophilic proteinaceous material and erythrocytes (hemorrhage).
Pituitary, Rathke's cleft - Dilation in a female F344/N rat from a chronic study. The dilated Rathke's cleft contains pale eosinophilic proteinaceous material and erythrocytes (hemorrhage).

Authors

Robert R. Maronpot, DVM, MS, MPH, DACVP, DABT, FIATP
Senior Pathologist
Experimental Pathology Laboratories, Inc.
Research Triangle Park, NC

Amy Brix, DVM, PhD, DACVP
Senior Pathologist
Experimental Pathology Laboratories, Inc.
Research Triangle Park, NC

Reviewers

Thomas J. Rosol, DVM, PhD, DACVP
Professor of Veterinary Biosciences
Senior Advisor, Life Sciences, Technology Commercialization and Knowledge Transfer
The Ohio State University
Columbus, OH

Deepa B. Rao, BVSc, MS, PhD, DABT, DACVP
NTP Pathologist (Contractor)
Integrated Laboratory Systems, Inc.
Research Triangle Park, NC