Re-examination of the Discrepancy Between Acidophil Numbers and Growth Hormone Concentration in the Anterior Pituitary Gland Following Thyroidectomy

Schooley, Robert A.; Friedkin, Stephen; Evans, Edward S.

doi:10.1210/endo-79-6-1053

Cited by 43 publications

(20 citation statements)

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“…Potvliege (1968) claimed that the degranulated acidophils following thyroidectomy took an appearance of prolactin cells. Smith and Farquhar (1966) reported that when the secretory activity of the acidophils was generally suppressed the storage granules were fused with lysosomes. The present observations did not present any close relationship between lysosomes and prolactin granules.…”

Section: Discussionmentioning

confidence: 99%

“…It was also reported that after thyroidectomy the pituitary GH content was lowered while the serum GH activity was elevated (Contopoulos et al, 1958;Solomon and Greep, 1959;Amerbury et al, 1965;Schooley et al, 1966). Ishikawa et al(1972) centrifuged pellets of the isolated acidophils less contaminated with the cells of other kind and classified acidophil granules into two patterns according to their diameter; the large ones approximately 350 m,u and the small ones, about 130 my.…”

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confidence: 99%

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Fine Structure of Pituitary Acidophils in Thyroidectomized Rats with or without the Treatment with Thyroxine and Dexamethasone

Harumiya

1972

Endocrinol Japon

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SynopsisElectron microscopic study was made on rat anterior pituitaries in an attempt to clarify the causal mechanism of "loss of acidophils" which could be detected with the light microscope following thyroidectomy. In the advancing days after thyroidectomy, the acidophils (somatotrophs) were gradually deprived of their large granules whose diameter was about 350 mu. There was evidence in vivo for the first time that there were some acidophils containing only the small granules, about 130 mu in diameter, after the 7th postoperative day. This clearly showed the simultaneous existence of two different sizes of granules in the same acidophils. As time elapsed, the large granules dispersed from the acidophils. After the 30th day these acidophils began to adjust their shape into the polygonal cells. Eventually, the acidophils completely lacking granules of either size occassionally appeared on the 90th and 200th days. Thus thyroidectomy had a strong influence to release the large granules, whereas an influence to release the small ones was not remarkable. The replacement injection of thyroxine into the thyroidectomized rats efficaciously reproduced the large granules which were generally considered to be responsible for GH storage. The repeated administrations of dexamethasone to the thyroidectomized rats resulted in the increase in number of small granules that were thought by us to be the storage carriers of ACTH. On the other hand, this compound alleviated loss of large granules following thyroidectomy. The final fate of acidophils after thyro:c.ectomy was, however, still vague because of the equivocal distinguishment of these degranulated acidophils from the immature basophils. Thus, the "loss of acidophils" may not mean the intrinsic disappearance of the cells themselves, but represent a transient loss of the large dense granules in the remaining acidophils.

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Section: Discussionmentioning

confidence: 99%

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confidence: 99%

Fine Structure of Pituitary Acidophils in Thyroidectomized Rats with or without the Treatment with Thyroxine and Dexamethasone

Harumiya

1972

Endocrinol Japon

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“…Influence of L-T3 on growth hormone induction and thyroid hormone receptor depletion in dispersed rat anterior pituitary cells. In the rat, thyroidectomy markedly lowers the pituitary and serum growth hormone content, and this is rapidly restored by thyroid hormone administration (9)(10)(11)(12). The onset and timecourse of growth hormone accumulation in GH, cells (36) and in the rat pituitary in vivo (12) are essentially identical, which suggests that thyroid hormone induces this response by the same mechanism in GH, cells and the pituitary somatotroph.…”

Section: Introductionmentioning

confidence: 97%

“…In this system, L-triiodothyronine (L-T3)1 stimulates a 3-to 10-fold increase in the rate of growth hormone synthesis (2,5,7) which is paralleled by changes in total cytoplasmic growth hormone imessenger RNA (mRNA) levels (8). The physiological relevence of this effect in GH1 cells is underscored by the observation that thyroid hormone plays an important role in controlling the production of growth hormone in the rat pituitary in vivo (9)(10)(11)(12), although thyroid growth hormone has been reported to have an equivocal effect on growth hormone production in dispersed anterior pituitary cells in vitro (13).…”

Section: Introductionmentioning

confidence: 99%

Relationship of receptor affinity to the modulation of thyroid hormone nuclear receptor levels and growth hormone synthesis by L-triiodothyronine and iodothyronine analogues in cultured GH1 cells.

Samuels¹,

Stanley²,

Casanova³

1979

J. Clin. Invest.

122

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A B S T R A C T We have previously demonstrated that L-triiodothyronine (L-T3) induces an increase in growth hormone synthesis and messenger RNA in cultured GH1 cells, a rat pituitary cell line. In addition to regulating the growth hormone response, L-T3 elicits a time-and dose-dependent reduction in the level of its nuclear receptor, which is a direct function of the occupancy of the receptor binding site. In this study we have compared the relative affinity of L-T3, triiodothyroacetic acid, D-triiodothyronine (D-T3), and L-thyroxine (L-T4) for the receptor with the induction ofthe growth hormone synthesis and the ability of these compounds to elicit a reduction in thyroid hormone nuclear receptor levels. Triiodothyroacetic acid and D-T3 were specifically examined because the biologic effect of these compounds in the intact rat is significantly lower than predicted by their affinity for the receptor using isolated rat liver nuclei in vitro. In intact cells each compound demonstrated an excellent relationship between the relative receptor affinity, the induction of growth hormone production, and the concentration-dependent reduction in nuclear receptor levels. With the exception of D-T3, the relative affinity of iodothyronine was identical for the receptor using intact cells in serum-free media, or isolated GH, cell nuclei in vitro. The apparent receptor affinity of D-T3 with intact cells was 5.5-fold lower than with isolated nuclei, which suggests a decrease in cell entry of D-T3 relative

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“…The hormonal influences such as thyroxine, insulin, gonadal hormones (Pecile and Muller, 1966;Reichlin, 1966;Schooley et al, 1966) and GH (Krulich and McCann, 1966a ;Muller et al, 1967a) are involved as the factors regulating GH secretion. Starvation (Roth et al, 1963), a variety of non-specific stimuli (Krulich and McCann, 1966b;Muller et al, 1967b, c) and moderate exercise (Hunter et al, 1965) also altered GH secretion.…”

Section: Discussionmentioning

confidence: 99%

Age-, Strain-, and Sex-Differences in the Anterior Pituitary Growth Hormone Content of Mice

Yanai

Nagasawa

1968

Endocrinol Japon

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SYNOPSISThe growth, the anterior pituitary weight, and the anterior pituitary growth hormone (GH) content of C3H/He and C57BL/6 strains of mice were investigated during 12-120 days of age in the male and 30-90 days of age in the female. The pituitary GH content was measured by disc electrophoresis. The pattern of growth and the increasing rate of body weight were similar in either strain, whereas the body weight of C3H/He was always greater than that of C57BL/6 in both sexes. The whole pituitary weight increased with age until 40-60 days and became plateau thereafter in the male of both strains and the C57BL/6 female. On the other hand, the pituitary weight of the C3H/He female continued to increase until the 90th day. Although the pituitary weights were greater in C3H/He than in C57BL/6 until the 60th and 90th days of age in both sexes the pattern of its change was little different according to the strains. The variation of the relative pituitary weight per 10g body was not so remarkable with age in both strains and sexes. In both strains, the total GH content and the relative GH content per 10g body changed in a similar pattern with age, which increased until 50-60 days of age and became plateau or inclined to decrease a little after that in the male, while they continued to increase until the 90th day in the female. The total GH content in C3H/He was significantly higher than that in C57BL/6 in either sex. The relative GH content per 10g body showed no difference between strains in the male, but it was higher in C3H/He than in C57BL/6 in the female. In C3H/He, the female excelled the male not only in the total GH content but also in the GH content per observed in these areas in C57BL/6. The GH content per mg pituitary showed no noticeable variations with age, strain and sex. The significance of these findings was discussed.There is experimental evidence to show that growth hormone (OH) is essential for growth process, general metabolism, mammary gland development and lactation on which the mechanisms of GH action are not always completely clear. Further, the accerelating effect of GH on transplantable mammary tumor growth of mice has been reported (Speiser et al., 1966).The authors demonstrated that the C3H/He strain (a high mammary tumor strain) was superior to the C57BL/6 strain (a low mammary tumor strain) in growth, mammary gland development and lactational performance (Nagasawa et al., 1967a, b, c), and it was thought worthwhile to study the difference

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Re-examination of the Discrepancy Between Acidophil Numbers and Growth Hormone Concentration in the Anterior Pituitary Gland Following Thyroidectomy

Cited by 43 publications

References 1 publication

Fine Structure of Pituitary Acidophils in Thyroidectomized Rats with or without the Treatment with Thyroxine and Dexamethasone

Fine Structure of Pituitary Acidophils in Thyroidectomized Rats with or without the Treatment with Thyroxine and Dexamethasone

Relationship of receptor affinity to the modulation of thyroid hormone nuclear receptor levels and growth hormone synthesis by L-triiodothyronine and iodothyronine analogues in cultured GH1 cells.

Age-, Strain-, and Sex-Differences in the Anterior Pituitary Growth Hormone Content of Mice

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