Myelinated Herring bodies in the posterior part of the median eminence of the mouse

1981 ◽  
Vol 219 (1) ◽  
Author(s):  
Y. Yamazaki ◽  
K. Shimizu ◽  
H. Keino ◽  
A. Mizutani
Keyword(s):  
Median Eminence ◽  
Posterior Part ◽  
Herring Bodies

PERMANENT ISOLATION OF THE ADENOHYPOPHYSIS FROM HYPOTHALAMIC CONTROL IN RATS WITH DIABETES INSIPIDUS

1964 ◽  
Vol 30 (3) ◽  
pp. 377-NP
Author(s):  
G. C. KENNEDY ◽  
R. A. PARKER
Keyword(s):  
Diabetes Insipidus ◽  
Median Eminence ◽  
Posterior Part ◽  
Normal Weight ◽  
Aldehyde Fuchsin ◽  
Thyroid Uptake ◽  
Electrolytic Lesions ◽  
Cytological Changes ◽  
The Difference ◽  
Portal Veins

SUMMARY Electrolytic lesions in the posterior part of the median eminence of rats caused diabetes insipidus, and aldehyde-fuchsin-positive material disappeared from the infundibular process but not from the hypothalamus. The lesions were consistently followed by infarction of the central pars distalis and depression of the thyroid uptake of radioactive iodine, but the effects on the gonads and adrenal cortex were very variable. Chronic adrenal atrophy occurred in some females in association with recurrent pseudopregnancy, atrophic but hyperluteinized ovaries, and cytological changes in the pituitary similar to those in ectopic grafts. After a short post-operative period of pseudopregnancy other rats recovered normal cycles and had, in general, adrenals of normal weight; their pituitaries resembled ectopic grafts returned to the median eminence. It is suggested that the difference between the two groups of rats with chronic lesions depended on the permanence or otherwise of the damage to the long portal veins. No evidence could be found of a separate corticotrophin-releasing mechanism in the median eminence, nor of any dependence of the secretion of corticotrophin on the release of vasopressin.

Ultrastructural Localization of Acetylcholinesterase in the Arcuate Nucleus and Median Eminence of the Rat

1977 ◽  
Vol 35 ◽  
pp. 440-441
Author(s):  
K.A. Carson ◽  
C.B. Nemeroff ◽  
M.S. Rone ◽  
J.S. Kizer ◽  
J.S. Hanker
Keyword(s):  
Choline Acetyltransferase ◽  
Median Eminence ◽  
Arcuate Nucleus ◽  
Cholinergic Neurons ◽  
Ultrastructural Localization ◽  
Male Rats ◽  
Neonatal Rats ◽  
Good Marker ◽  
Chemical Studies ◽  
High Doses

Biochemical, physiological, pharmacological, and more recently enzyme histo- chemical data have indicated that cholinergic circuits exist in the hypothalamus. Ultrastructural correlates of these pathways such as acetylcholinesterase (AchE) positive neurons in the arcuate nucleus (ARC) and stained terminals in the median eminence (ME) have yet to be described. Initial studies in our laboratories utilizing chemical lesioning and microdissection techniques coupled with microchemical and light microscopic enzyme histo- chemical studies suggested the existence of cholinergic neurons in the ARC which project to the ME (1). Furthermore, in adult male rats with Halasz deafferentations (hypothalamic islands composed primarily of the isolated ARC and the ME) choline acetyltransferase (ChAc) activity, a good marker for cholinergic neurons, was not significantly reduced in the ME and was only somewhat reduced in the ARC (2). Treatment of neonatal rats with high doses of monosodium 1-glutamate (MSG) results in a lesion largely restricted to the neurons of the ARC.

Fine structure of the rectal papillae of the oriental fruuit fly, Dacus dorsalis Hendel (Tephritidae, Diptera Insecta)

1990 ◽  
Vol 48 (3) ◽  
pp. 498-499
Author(s):  
Len Wen-Yung ◽  
Mei-Jung Lin
Keyword(s):  
Fine Structure ◽  
Cell Membrane ◽  
Intercellular Space ◽  
Anterior Part ◽  
Apical Cell ◽  
Posterior Part ◽  
Apical Cell Membrane ◽  
Dacus Dorsalis ◽  
Radial Cell ◽  
Circular Base

Four cone-shaped rectal papillae locate at the anterior part of the rectum in Dacus dorsalis fly. The circular base of the papilla protrudes into the haemolymph (Fig. 1,2) and the rest cone-shaped tip (Fig. 2) inserts in the rectal lumen. The base is surrounded with the cuticle (Fig. 5). The internal structure of the rectal papilla (Fig. 3) comprises of the cortex with the columnar epithelial cells and a rod-shaped medulla. Between them, there is the infundibular space and many trabeculae connect each other. Several tracheae insert into the papilla through the top of the medulla, then run into the cortical epithelium and locate in the intercellular space. The intercellular sinuses distribute in the posterior part of the rectal papilla.The cortex of the base divides into about thirty segments. Between segments there is a radial cell (Fig. 4). Under the cuticle, the apical cell membrane of the cortical epithelium is folded into a regular border of leaflets (Fig. 5).

What Is Left Is Right

2009 ◽  
Vol 14 (1) ◽  
pp. 78-89 ◽  
Author(s):  
Kenneth Hugdahl ◽  
René Westerhausen
Keyword(s):  
Speech Processing ◽  
Information Transfer ◽  
Hemispheric Asymmetry ◽  
Functional Neuroimaging ◽  
Gray Matter Volume ◽  
Functional Anatomy ◽  
Posterior Part ◽  
Functional Asymmetry ◽  
Planum Temporale ◽  
Evolution Of Speech

The present paper is based on a talk on hemispheric asymmetry given by Kenneth Hugdahl at the Xth European Congress of Psychology, Praha July 2007. Here, we propose that hemispheric asymmetry evolved because of a left hemisphere speech processing specialization. The evolution of speech and the need for air-based communication necessitated division of labor between the hemispheres in order to avoid having duplicate copies in both hemispheres that would increase processing redundancy. It is argued that the neuronal basis of this labor division is the structural asymmetry observed in the peri-Sylvian region in the posterior part of the temporal lobe, with a left larger than right planum temporale area. This is the only example where a structural, or anatomical, asymmetry matches a corresponding functional asymmetry. The increase in gray matter volume in the left planum temporale area corresponds to a functional asymmetry of speech processing, as indexed from both behavioral, dichotic listening, and functional neuroimaging studies. The functional anatomy of the corpus callosum also supports such a view, with regional specificity of information transfer between the hemispheres.

HYPERTROPHIC ADRENALS AND THEIR RESPONSE TO STRESS AFTER LESIONS IN THE MEDIAN EMINENCE OF TOTALLY HYPOPHYSECTOMIZED PIGEONS

1961 ◽  
Vol 37 (4) ◽  
pp. 565-576 ◽  
Author(s):  
Richard A. Miller
Keyword(s):  
Dose Response ◽  
Median Eminence ◽  
Response Curve ◽  
Liver Parenchyma ◽  
Dose Response Curve ◽  
Pars Distalis ◽  
Adrenal Enlargement ◽  
Response To Stress ◽  
Lethal Doses ◽  
Chromaffin Tissue

ABSTRACT Four per cent formaldehyde, insulin, or epinephrine in oil was injected for 5 days into pigeons subjected to varying degrees of hypophysectomy alone or together with large lesions in the median eminence and hypothalamus. Adrenals atrophied after the removal of the pars distalis alone or together with the neurohypophysis in untreated pigeons but showed markedly hypertrophic interrenal tissue (cortex in mammals) after treatment with formaldehyde or insulin. The slope of the dose-response curve was similar in operated and unoperated pigeons. The accumulation of bile in the liver parenchyma, which may occur after removal of the pars distalis, is an endogenous stress which was associated regularly with adrenal hypertrophy. After very large lesions of the median eminence and ventral hypothalamus in addition to total hypophysectomy, adrenals hypertrophied rather than atrophied, and the response to formaldehyde paralleled that in intact and »hypohysectomized« pigeons. Interrenal tissue was stimulated regularly; chromaffin tissue was partially degranulated, sometimes showed hyperplasia with colchicine, but only occasionally appeared hypertrophied. Epinephrine in nearly lethal doses caused only minimal adrenal enlargement. After adrenal denervation followed by hypophysectomy, the adrenals were still stimulated by formaldehyde. It appears that the interrenal tissue of the pigeon responds to a humoral stimulus not of hypophyseal origin in the absence of the hypophyseal-hypothalamic system.

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

1962 ◽  
Vol 39 (1) ◽  
pp. 13-21 ◽  
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.

THE RELATION BETWEEN THE HYPOTHALAMIC NEUROSECRETION AND THE CORTICOTROPHIN RELEASE IN EXPERIMENTAL CONDITIONS

1960 ◽  
Vol XXXIV (I) ◽  
pp. 8-18 ◽  
Author(s):  
E. Kivalo ◽  
U. K. Rinne
Keyword(s):  
Paraventricular Nucleus ◽  
Median Eminence ◽  
Supraoptic Nucleus ◽  
Acute Stress ◽  
Neurosecretory Material ◽  
Experimental Conditions ◽  
Hypothalamic Cells ◽  
The One ◽  
Hypophysial Portal ◽  
Acth Release

ABSTRACT Acute stress, chronic stress plus hydration, cortisone treatment, cortisone treatment plus dehydration were used as methods of investigation and the relation between the neurosecretory activity of the hypothalamic supraoptic nucleus and paraventricular nucleus and the neurosecretory material around the hypophysial portal vessels of the median eminence on the one hand and the corticotrophin release on the other hand, has been studied in the rat. Whereas stress stimulates both the activity of the above mentioned cells of the hypothalamus and the ACTH release, stress plus hydration causes a depression of these hypothalamic cells but nevertheless causes a marked ACTH release. Cortisone inhibits the activity of the cells in the supraoptic nucleus and the paraventricular nucleus as well as the ACTH release whereas cortisone plus dehydration causes stimulation but inhibits the ACTH release. In some stress and cortisone treatment groups the variations of the neurosecretory material around the hypophysial portal vessels and of the ACTH release were found to show a correlation. It is concluded that the activity of the cells of the supraoptic nucleus and the paraventricular nucleus and the ACTH release do not seem to have any definite connection, whereas some observations indicate that the neurosecretory material in the region of the median eminence around the hypophysial portal vessels may have some significance in ACTH release.

TUNGAU PADA DAUN MANGGA (Mangifera Indica)

2014 ◽  
Vol 13 (3) ◽  
Author(s):  
Rawati Panjaitan
Keyword(s):  
Life Cycle ◽  
Direct Observation ◽  
Host Plants ◽  
Body Shape ◽  
Leaf Surface ◽  
Mangifera Indica ◽  
Posterior Part ◽  
Mango Leaves

Mites have hostplant specifications or host plants. Mites can be destructive and deadly of which is the host plants a mango crop. Mites on mango crops will cause the leaves yellow and fall off prematurely. This is will lead to the disruption of the productivity of mango. It is necessary for research to identify the mites that infect the mango crop. The method is carried out by direct observation. Mites were taken from the surface of mango leaves later in preservation with several levels of concentration of alcohol, and polyvinyl laktofenol. Then, observed under a microscope and documented for identification purposes. Mites on the leaf surface of manalagi mango (<em>Mangifera indica</em>) found two species, it is <em>Oligonychus</em> sp. and <em>Oligonychus ilicis</em> (Family: Tetranychidae, Superfamily: Tetranychoidea). <em>Oligonychus</em> sp. hallmark is rounded body shape like a spider, with a body is transparent and there are two long seta on posterior part. While <em>Oligonychus ilicis</em> has a characteristic elongated rounded body shape, red, and there is a short posterior seta. <em>Oligonychus</em> sp. and <em>Oligonychus ilicis</em> live as parasites on the surface of mango leaves that can lead to wrinkled leaves, yellow and to fall. <em>Oligonychus</em> life cycle starts from the eggs develop into Nympha and then adult.

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