Histamine Releasing Factors

The morphologic effects on somatotrophs of crude sheep hypothalamic extract prepared from stalk-median eminence were studied by electron microscopy in conjunction with concurrently run bioassays performed on the same tissue samples taken from young adult male Sherman rats.Groups were divided into uninjected controls and injected experimentals sacrificed at 5', 15', and 30' after injection. Half of each anterior pituitary was prepared for electron microscopic investigation, the other half for bioassay. Fixation using collidine buffered osmium tetroxide was followed by dehydration and embedment in Maraglas. Uranyl acetate and lead citrate were used as stains. Thin sections were examined in a Philips EM 200.Somatotrophs from uninjected controls appeared as described in the literature (Fig. 1). In addition to other components, these cells contained moderate numbers of spherical, electron-dense, membrane-bound granules approximately 350 millicrons in diameter.

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THE EFFECT OF HYPOTHALAMIC LESIONS ON REPRODUCTIVE ACTIVITY IN SHEEP

Journal of Endocrinology ◽

10.1677/joe.0.0390415 ◽

1967 ◽

Vol 39 (3) ◽

pp. 415-NP ◽

Cited By ~ 10

Author(s):

H. M. RADFORD

Keyword(s):

Median Eminence ◽

Reproductive Activity ◽

Mammillary Body ◽

Optic Chiasma ◽

Hypothalamic Lesions ◽

Apparent Change ◽

Electrolytic Lesions ◽

Releasing Factors ◽

Bilateral Lesions ◽

Made In

SUMMARY Electrolytic lesions were made in the hypothalamus of 41 Merino ewes which were subsequently observed for 2–16 months. Ovarian inactivity resulted from bilateral medial and ventral lesions placed immediately posterior to the optic chiasma (four ewes) or immediately anterior to the mammillary body (five ewes). Failure to show oestrus while apparently still ovulating regularly was a feature in another four ewes in which bilateral medial and ventral lesions were placed between the sites already described. Small bilateral lesions in these ventral regions led initially to ovarian inactivity, but final re-establishment of apparently normal reproductive activity in three ewes. Bilateral lesions in regions other than those described above resulted in no apparent change in reproductive activity (eight ewes). Similarly, unilateral or asymmetrical lesions in the remaining 17 ewes failed to affect their reproductive activity. The results are consistent with the hypothesis that in sheep a region of the median eminence responsible for the production of gonadotrophin-releasing factors requires neural inputs traversing both anterior and posterior hypothalamic areas.

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447 Atopic dermatitis (AD) and histamine releasing factors (HRFs): Effect on human skin mast cells (HSMC)

Journal of Allergy and Clinical Immunology ◽

10.1016/0091-6749(91)91730-h ◽

1991 ◽

Vol 87 (1) ◽

pp. 251

Author(s):

S ZEKOWSKI ◽

R OTTE ◽

M THARP ◽

P FIREMAN

Keyword(s):

Atopic Dermatitis ◽

Mast Cells ◽

Human Skin ◽

Releasing Factors

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Differences in the degradation of hypothalamic releasing factors by rat and human serum

Life Sciences ◽

10.1016/0024-3205(76)90263-0 ◽

1976 ◽

Vol 19 (8) ◽

pp. 1271-1276 ◽

Cited By ~ 51

Author(s):

Myron Benuck ◽

Neville Marks

Keyword(s):

Human Serum ◽

Releasing Factors

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THE ACTION OF SOME OVULATION INHIBITORS ON THE RABBIT HYPOTHALAMUS

Acta Endocrinologica ◽

10.1530/acta.0.0660221 ◽

1971 ◽

Vol 66 (2) ◽

pp. 221-228 ◽

Cited By ~ 5

Author(s):

Dona A. Frith ◽

K. C. Hooper

Keyword(s):

Enzyme Activity ◽

Hormone Secretion ◽

Chlormadinone Acetate ◽

Releasing Factors ◽

Sites Of Action ◽

Ethinyl Oestradiol

ABSTRACT The previous paper (Frith & Hooper 1971) described the activities of certain hypothalamic enzymes at various times after mating and it was suggested that changes in enzymes levels may be used as an index of the release of gonadotrophic hormones. Using this approach, a study has been made of the action of the ovulation inhibitors chlormadinone acetate, norethindrone, ethinyl oestradiol and oestrone on the rabbit hypothalamus. The four inhibitors increased enzyme activity in the hypothalamus. Previous work has shown that raised levels of enzyme activity are associated with a lowered level of gonadotrophic hormone secretion. It is suggested, therefore, that one of the sites of action of the inhibitors is on polypeptide turnover in the hypothalamus, and it seems possible that this is one of the factors controlling the availability of gonadotrophin releasing factors.

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Growth hormone releasing factors and secretion of growth hormone in sheep, calves and pigs

Domestic Animal Endocrinology ◽

10.1016/0739-7240(86)90004-4 ◽

1986 ◽

Vol 3 (3) ◽

pp. 165-176 ◽

Cited By ~ 21

Author(s):

M.A. Della-Fera ◽

F.C. Buonomo ◽

C.A. Baile

Keyword(s):

Growth Hormone ◽

Releasing Factors

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Diseases of hypothalamic releasing factors

Disease-a-Month ◽

10.1016/s0011-5029(76)80003-x ◽

1976 ◽

Vol 22 (6) ◽

pp. 1-37 ◽

Cited By ~ 3

Author(s):

Lawrence A. Frohman

Keyword(s):

Releasing Factors

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The Adrenocortical Function Studies in Children

Paediatrica Indonesiana ◽

10.14238/pi15.3-4.1975.120-4 ◽

2017 ◽

Vol 15 (3-4) ◽

pp. 120

Author(s):

Iwao Takakura

Keyword(s):

Neonatal Period ◽

Clinical Work ◽

Adrenocortical Function ◽

Chemical Structures ◽

Pediatric Age Group ◽

Loading Tests ◽

Laboratory Procedures ◽

Radio Immunoassay ◽

Releasing Factors

The recent advances in the laboratory procedures make it possible to study endocrinological states in children more easily and more accurately even in the neonatal period. The successes in purification and the determination of chemical structures of various hormones and their releasing factors make it possible to carry out various loading tests. The progress in the measurement of various hormones and their metabolites especially in the field of radioimmunoassay is really remarkable.If we took adrenocortical function studies as an example, urinary 17 hydroxycorticosteroid was the only reliable item about ten years ago, then plasma 17-OHCS determination using Porter-Silver chromogen was introduced followed by plasma 11-OHCS determination with fluorescence spectrophotometry. Then, cortisol production rate determination became possible using radio-isotope dilution technique, and at present, plasma cortisol can be measured directly with protein competitive radio-immunoassay. Thus, the adrenocortical function studies in the pediatric age group has become easier and more reliable. The author likes to present some endocrinological results in children using various methods and now they can be applied in the clinical work.

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