Calcium/calmodulin-dependent kinases can regulate the TSH expression in the rat pituitary

Follicular structures, in the rat pituitary, composed of cells joined by junctional complexes and possessing few organelles and few, if any, secretory granules, were first described by Farquhar in 1957. Cells of the same description have since been observed in several species including man. The importance of these cells, however, remains obscure. While studying human pituitary glands, we have observed wide variations in the fine structure of follicular cells which may lead to a better understanding of their morphogenesis and significance.

Download Full-text

Ultrastructural Immunocytochemistry of Five Rat Pituitary Adenomas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600003147 ◽

1980 ◽

Vol 38 ◽

pp. 724-725

Author(s):

D. J. McComb ◽

N. Ryan ◽

E. Horvath ◽

K. Kovacs ◽

E. Nagy ◽

...

Keyword(s):

Pituitary Adenomas ◽

Pituitary Tumors ◽

Electron Microscopic ◽

Electron Microscopic Immunocytochemistry ◽

Transmission Electron ◽

Rat Pituitary ◽

Radiation Induced ◽

Group 5 ◽

Group 2 ◽

Microscopic Techniques

Conventional light and electron microscopic techniques failed to clarify the cellular composition and derivation of spontaneous and induced, intrasellar and transplanted pituitary adenomas in rats (1). In the present work, electron microscopic immunocytochemistry was applied to evaluate five adenohypo-physial tumors using a technique described by Moriarty and Garner (2). Spontaneously occurring pituitary adenomas (group 1) were harvested from aging female Long-Evans rats. R-Amsterdam rats were treated with 2 x 1.0 mg estrone acetate (HogivaI) s.c. weekly for 6 months. Pituitary adenomas in excess of 30 mg were removed from these animals to make up the tumors of group 2. Groups 3 and 4 consisted of estrogen-induced autonomous transplan¬ted pituitary tumors MtT.WlO and MtT.F4. Group 5 was a radiation-induced transplanted autonomous pituitary tumor MtT.W5. The tumors of groups 3,4 and 5 were allowed to proliferate in host rats 6-8 weeks prior to removal for processing. Tissue was processed for transmission electron microscopy (glutaraldehyde fixation, OsO4 postfixation and epoxy resin embedding), and electron microscopic immunocytochemistry (3% paraformaldehyde fixation and Araldite embedding).

Download Full-text

Effects of Cimicifuga racemosa extracts on estrogen responsive genes in rat pituitary gland in vitro and in vivo

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/s-2005-862976 ◽

2005 ◽

Vol 113 (S 1) ◽

Author(s):

J Wober ◽

M Krumbholz ◽

G Vollmer

Keyword(s):

Pituitary Gland ◽

Cimicifuga Racemosa ◽

Rat Pituitary

Download Full-text

ADENOHYPOPHYSEAL LH CONTENT IN NORMAL, ANDROGEN-STERILIZED AND PROGESTERONE-PRIMED STERILE FEMALE RATS

Acta Endocrinologica ◽

10.1530/acta.0.0390013 ◽

1962 ◽

Vol 39 (1) ◽

pp. 13-21 ◽

Cited By ~ 19

Author(s):

Roger A. Gorski ◽

Charles A. Barraclough

Keyword(s):

Ascorbic Acid ◽

Electrical Stimulation ◽

Quantitative Determination ◽

Median Eminence ◽

Hypothalamic Stimulation ◽

Female Rats ◽

Rat Pituitary ◽

Gland Content ◽

Stimulation Of

ABSTRACT We have previously suggested that the failure of the androgen-sterilized, persistent-oestrous rat to ovulate, following electrical stimulation of the median eminence structures of the hypothalamus, is due to an insufficiency in adenohypophyseal LH concentration. Using the ovarian ascorbic acid technique for quantitative determination of pituitary LH content, the present studies have demonstrated that the sterile rat pituitary gland contains one-third the LH content of the normal prooestrous gland. Furthermore, not only does progesterone priming of this persistent-oestrous rat result in a 75 % increase in LH concentration, but on hypothalamic stimulation sufficient LH is released to induce ovulation. The decrease in LH concentration which accompanies ovulation in the progesterone-primed, sterile rat is approximately 45 % of the total gland content as compared with a 51 % decrease in pituitary content in the normal cyclic rat.

Download Full-text