Multiple forms of acth biological activity in the pars intermedia of the rat adenohypophysis

Zimmerman, Arthur E.; Kraicer, Jacob

doi:10.1016/0024-3205(78)90640-9

Cited by 13 publications

(14 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The function of the pars intermedia of the mammalian adenohypophysis is poorly understood as yet, though it is known that this tissue synthesizes and contains a series of hormonally active substances derived from a common precursor [Mains and Eipper, 1975;Eipper and Mains, 1978;Seidah et al, 1978;Zimmerman and Kraicer, 1978;Gianoulakis et al, 1979;Nakanishi et al, 1979;Mains and Eipper, 1979]. In contrast to other endocrine tissues, the pars inter media in many mammals has a poor to virtuallv non-existent vascular supply {Howe and Maxwell, 1968;Howe, 1973;Murakami, 1975].…”

Section: Introductionmentioning

confidence: 99%

Scanning Electron Microscopy of Rat Neurointermediate Lobe Cells in Culture

Zimmerman¹,

Milligan²,

Joneja

1981

Cells Tissues Organs

Self Cite

View full text Add to dashboard Cite

Enzymatically dispersed cells of the rat pars nervosa – pars intermedia (NI) were observed by scanning electron microscopy after 1, 2 and 4 days in culture. The cells attached to the plate slowly, requiring about 3–4 days for the majority to adhere. The epithelial cells became attached singly and in clumps and branched chains, often over a bed of fibroblast-like cells. After the first day in culture, few surface features were evident on the NI cells, but by day 2, the surfaces showed a small number of blebs. In 4-day cultures, the cells revealed extensive areas with blebs and microvilli, and a few structures resembling cilia were observed. The adrenocorticotrophic hormone content of the cells after 4 days in culture was similar to that found in fresh tissue.

show abstract

Section: Introductionmentioning

confidence: 99%

Scanning Electron Microscopy of Rat Neurointermediate Lobe Cells in Culture

Zimmerman¹,

Milligan²,

Joneja

1981

Cells Tissues Organs

Self Cite

View full text Add to dashboard Cite

show abstract

“…These results agree with those reported for adults of other species. In the extracts of intermediate lobe of adult rats or in the incu bation medium of isolated intermediate lobe cells, three peaks of ACTH were found; the highest was 'big' ACTH [27,48] [31] detected two ACTH forms with molecular weights of 27.000 and 4,800. In the neurointermediatc lobe of adult rat 'big' ACTH was the predominant form.…”

Section: Discussionmentioning

confidence: 99%

“…28]. Later on, Zimmerman and Kraicer [48] using simi lar techniques of filtration, showed that ex tracts of the rat anterior lobe contained three peaks of ACTH: peak I eluted near the void volume, peak III coeluted with ACTH|_39 and peak II eluted midway between the void volume and ACTH|_39; peaks II and III were predominant in the anterior lobe extract. In the rat anterior lobe, four different species of ACTH were described as having molecular weights of 31,000, 21,000.…”

Section: Discussionmentioning

confidence: 99%

“…Unlike 'big' ACTH, 'little' or 'intermediate' ACTH had a strong biological activity. 'Big' ACTH was quantitatively important but showed low biological activity in pituitary extracts of rat [48] or mouse [31] as well as in mouse pitu itary tumor cells [31] 23.000-ACTH and glycosy lated ACTH,_39 or 13,000-ACTH) were able to stimulate corticosterone release; however, pro-ACTH/endorphin and the glycosylated ACTH|_39 were 100-and 300-fold less potent than ACTH 1.39 [15]. Later on.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Adrenocorticotrophic Hormone in the Anterior and Neurointermediate Lobes of the Rat during the Perinatal Period: Polymorphism, Biological and Immunological Activities of ACTH

Chatelain¹,

Dupouy²

1985

Neonatology

View full text Add to dashboard Cite

When acid extracts (0.1 NHCl) of the anterior or neurointermediate lobes of fetal and newborn rat pituitary were subjected to gel filtration on Sephadex G-50 fine columns, polymorphism of ACTH was revealed by radioimmunoassay. At every stage of pregnancy and after birth three main ACTH forms were observed. The first form (‘big’ ACTH) eluted near the void volume of the column; its apparent molecular weight was 45,000. The second form (‘little’ ACTH) coeluted with synthetic human ACTH_1–39 and ¹²⁵I human ACTH. As the latter marker eluted more slowly than the former, ‘little’ ACTH, which showed an apparent molecular weight near 5,000, could not be a single entity. The third form (‘intermediate’ ACTH) eluted between ‘big’ and ‘little’ ACTH; its apparent molecular weight was near 13,000. During the perinatal period, the relative proportions between these different molecular forms of ACTH changed in both anterior and neurointermediate lobes. Thus the gradual increase of ‘intermediate’ and ‘little’ forms was accompanied by a decrease of ‘big’ ACTH. The perfusion of fetal adrenal glands with the same immunological quantities of ‘big’, ‘intermediate’ and ‘little’ ACTH showed that the ‘little’ and ‘intermediate’ forms have greater biological potency in eliciting corticosterone secretion than the ‘big’ ACTH form.

show abstract

“…The recent findings of vascular interconnec tions between posterior lobe, median eminence and ante rior lobe [12] suggest that posterior lobe factors may also reach the anterior lobe and thus modulate corticotropin (ACTH) release. Posterior lobe factors which have been extracted include vasopressin and a CRF distinct from vasopressin [6,19], Moreover, the rat posterior lobe (neural lobe plus inter mediate lobe) secretes ACTH-like substances from the intermediate lobe [20] which may be controlled by acetyl choline, 5-Hydroxytryptamine and dopamine-containing nerve fibres [1,7, 10. 18].…”

mentioning

confidence: 99%

Release of Corticotropin and Corticotropin-Releasing Factors from Rat Posterior Pituitary <i>in vitro</i>

Bény¹,

Baertschi²

1980

Neuroendocrinology

View full text Add to dashboard Cite

Electrical stimulation of rat posterior lobes in vitro inhibited bioactive corticotropin (ACTH) release from the intermediate lobe and promoted the release of corticotropin-releasing factor(s) (CRF). Both effects were calcium dependent. Released posterior lobe CRF was inactivated by thioglycolate, and the CRF activity could be accounted for by vasopressin. Results suggest strongly that vasopressin is the predominant CRF released from neurohypophysial axons, and that intermediate lobe ACTH release is submitted to an inhibitory control.

show abstract

Multiple forms of acth biological activity in the pars intermedia of the rat adenohypophysis

Cited by 13 publications

References 24 publications

Scanning Electron Microscopy of Rat Neurointermediate Lobe Cells in Culture

Scanning Electron Microscopy of Rat Neurointermediate Lobe Cells in Culture

Adrenocorticotrophic Hormone in the Anterior and Neurointermediate Lobes of the Rat during the Perinatal Period: Polymorphism, Biological and Immunological Activities of ACTH

Release of Corticotropin and Corticotropin-Releasing Factors from Rat Posterior Pituitary <i>in vitro</i>

Contact Info

Product

Resources

About