SEASONAL CHANGES IN THE HYPOTHALAMOHYPOPHYSIAL NEUROSECRETORY SYSTEM OF DESERT RODENTS

1964 ◽  
Vol 29 (3) ◽  
pp. 251-NP ◽  
Author(s):  
F. KHALIL ◽  
J. TAUFIC
Keyword(s):  
Seasonal Changes ◽  
Morphological Characteristics ◽  
Maximal Activity ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Paraventricular Nuclei ◽  
Desert Rodents ◽  
Pars Nervosa ◽  
Increased Activity ◽  
Low Activity

SUMMARY Seasonal changes in the content of neurosecretory material in the supra-optic and paraventricular nuclei and in the pars nervosa of the desert rodents Jaculus jaculus (Oliv.) and Gerbillus gerbillus (Linn.) were followed and compared with those in the white rat kept under laboratory conditions. From the morphological characteristics it was concluded that neurosecretory activity in the desert rodent is minimal in December; signs of increased activity started in March, and maximal activity was reached in June. A decline of neurosecretory activity started in August and continued through the autumn season. In the laboratory white rat, on the other hand, the neurosecretory system showed low activity the whole year round. The quantity of neurosecretory material in the pars nervosa was less in summer than in winter.

Secretory Structures associated with the Neurosecretory System of the Immature Scorpion, Heterometrus swammerdami

1961 ◽  
Vol s3-102 (60) ◽  
pp. 475-479
Author(s):  
MOHAMMAD HABIBULLA
Keyword(s):  
Composite Structure ◽  
Secretory Activity ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Corpus Cardiacum ◽  
Secretory Structures ◽  
Moult Stage ◽  
Prothoracic Glands ◽  
Frontal Ganglion ◽  
Rostral Region

Certain previously unknown structures, probably endocrine in nature, are described. The blind ‘end-organ’ which is present and shows signs of activity in the pre-moult stage shows no noticeable sign of activity in the post-moult stage. In certain respects it is comparable to the ‘anterior organ’ of spiders, which has been homologized with the prothoracic glands of insects. In the rostral region of the scorpion, where the rostral nerve ramifies, an accumulation of leucocytes is found; these show signs of secretory activity. Both at the origin of the rostral nerve and also where it ramifies, neurosecretory material is seen. This rostral structure is comparable in certain aspects with the rostral organ of spiders. Leucocytes occur not only in the rostral organ but also in association with the ‘endorgan’. The presence of two ganglionic masses, above and below the stomodaeal commissure, suggests the possibility of the sympathetic (stomatogastric) ganglion of the scorpion being a composite structure consisting of the frontal ganglion, the corpus cardiacum, and possibly the hypocerebral ganglion. A hypocerebral ganglion is absent in the adult.

THE HYPOTHALAMO-HYPOPHYSIAL NEUROSECRETORY SYSTEM IN EXPERIMENTAL HYPERTENSION IN THE RAT

1963 ◽  
Vol 26 (1) ◽  
pp. 107-111 ◽  
Author(s):  
S. TALANTI ◽  
A. EISALO
Keyword(s):  
Marked Reduction ◽  
Ganglion Cells ◽  
Renal Hypertension ◽  
Nuclear Volume ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Experimental Hypertension ◽  
Experimental Conditions ◽  
Hypothalamic Nuclei ◽  
Experimental Renal Hypertension

SUMMARY The effect of experimental renal hypertension on the hypothalamo-hypophysial neurosecretory system was studied histologically. The amount of neurosecretory material decreased, especially in the neurohypophysis. A marked reduction in the nuclear volume of the neurosecretory ganglion cells occurred, while that of the cells of the other hypothalamic nuclei investigated remained unchanged. The results suggest that the activity of the neurosecretory system is diminished in the experimental conditions used.

The effect of feeding on the cerebral neurosecretory system of the adult male tsetse, Glossina austeni Newst

1978 ◽  
Vol 56 (9) ◽  
pp. 1988-1992 ◽  
Author(s):  
M. Grossman ◽  
K. G. Davey
Keyword(s):  
Adult Male ◽  
Neurosecretory Cells ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Corpus Cardiacum ◽  
Pars Intercerebralis ◽  
Corpora Cardiaca ◽  
Glossina Austeni ◽  
Effect Of Feeding

An analysis of the intensity of staining of the corpus cardiacum and of the neurosecretorty cells of the pars intercerebralis in 3-day-old fed or fasting adult male tsetse has revealed two periods of apparent release of neurosecretion. In fed males, stainable neurosecretion disappears from 14 of the 20 recognizable neurosecretory cells within 10 min of the termination of feeding. There is always less neurosecretory material in the corpora cardiaca of fed males. Secondly, there is an indication of a depletion of material from the cardiaca of both fed and fasted males at about 1700 hours EST.

Seasonal changes in the diel surfacing behaviour of the bimodally respiring turtle Rheodytes leukops

2003 ◽  
Vol 81 (9) ◽  
pp. 1614-1622 ◽  
Author(s):  
Matthew A Gordos ◽  
Craig E Franklin ◽  
Colin J Limpus
Keyword(s):  
Water Temperature ◽  
Seasonal Changes ◽  
Abiotic Factors ◽  
Diurnal Variations ◽  
Freshwater Turtle ◽  
Behavioural State ◽  
Pressure Sensitive ◽  
Diel Fluctuations ◽  
Increased Activity ◽  
Austral Autumn

The purpose of this study was to determine whether a relationship existed between the diel surfacing trends of the bimodally respiring freshwater turtle Rheodytes leukops and daily fluctuations in specific biotic and abiotic factors. The diel surfacing behaviour of adult R. leukops was recorded over four consecutive seasons (Austral autumn 2000 – summer 2001) within Marlborough Creek, central Queensland, Australia, using pressure-sensitive time–depth recorders. Additionally, diurnal variations in water temperature and aquatic PO2 level, as well as the turtle's behavioural state (i.e., active versus resting), were monitored. In autumn and summer, surfacing frequency increased significantly during the daylight hours, with peak levels normally occurring around dawn (0500–0700) and dusk (1700–1900). However, no consistent diel surfacing trend was recorded for the turtles in winter or spring, owing to considerable variation among individual R. leukops. Diurnal surfacing trends recorded for R. leukops in autumn and summer are attributed to periods of increased activity (possibly associated with foraging) during the daylight hours and not to daily variations in water temperature or aquatic PO2 level. Turtles generally remained at a depth greater than 1 m throughout the day, where the effect of diel fluctuations in water temperature (<0.5 °C) and aquatic PO2 level (<15 mm Hg (1 mm Hg = 133.322 Pa)) was considered to be negligible.

scholarly journals Morphological characteristics of the skin and hair of clinically healthy dogs and cats

2020 ◽  
pp. 80-84
Author(s):  
O. S. Snopenko ◽  
◽  
O. P. Timoshenko ◽  
A. Y. Ulyanitskaya ◽  
D. V. Kibkalo ◽  
...  
Keyword(s):  
Seasonal Changes ◽  
Morphological Characteristics ◽  
Punch Biopsy ◽  
Hair Follicles ◽  
Domestic Cat ◽  
Domestic Dogs ◽  
Skin Thickness ◽  
Sebaceous Glands ◽  
Histological Characteristics ◽  
Healthy Dogs

The article describes the histological characteristics of the skin of clinically healthy domestic dogs and cats, presents morphometric data on the thickness of the skin, layers of the epidermis, the area of the sebaceous glands and hair follicles; describes sexual and seasonal skin replacements in domestic dogs and cats, common in the east of Ukraine. The material for research is the skin of clinically healthy dogs and cats. Research method is histological. Punch-biopsy of skin fragments was performed in animals on the right from the middle of the lateral surface of the back. Fragments of skin after fixation in 10 % neutral formalin were examined by paraffin, followed by staining of slides with hematoxylin-eosin and by gelatin impregnation, staining with Sudan II, hematoxylin of Karachi. In horizontal and vertical skin sections, the following was investigated: the thickness of the epidermis, papillary and reticular layers, the length and width of the sweat and sebaceous glands, follicle of the hair, the location of hair bundles and the ratio of secondary follicles to primary ones. The histological characteristics of skin and derivatives in dogs and cats have been established. The information obtained from morphometric histostudies indicates significant fluctuations in the values in cats depending on the season; the difference in skin thickness in winter and summer reached 1407 μM and had the same parameters in females and males. The papillary and reticular layers of the dermis correlated with the total skin thickness as 53.9 and 60.3 % in winter and 45.4 and 38.7% in summer, respectively. Epidermal seasonal changes were less significant. The papillary layer of the skin of the domestic cat was more developed than the reticular layer, in contrast to the dogs. The area of the basal sebaceous glands in cats averaged 0.05 mm2 in summer and 0.013 mm2 in winter. In domestic dogs, skin thickness and hair density did not depend on seasonal changes, but on the sex of the animals; in females, the skin was on average 496 + 183 microns thick, and the density was not significantly higher than in males. The area of the sebaceous glands averaged 0,020 mm2 in dog, in cats 0.013 mm2 in summer and in winter – 0.05 mm2.

The Histology of the Neurosecretory System of the Adult Female Desert Locust, Schistocerca gregaria

1961 ◽  
Vol s3-102 (57) ◽  
pp. 27-38
Author(s):  
K. C. HIGHNAM
Keyword(s):  
B Cells ◽  
Cell Activity ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Desert Locust ◽  
Pars Intercerebralis ◽  
Secretory Cycle ◽  
Corpora Cardiaca ◽  
D Cells ◽  
A And B Cells

The pars intercerebralis of the brain of the desert locust contains about 2,400 cells in two groups, which stain with chrome-haematoxylin-phloxin and with paraldehydefuchsin. On the basis of differences in size and staining reactions, four types of cell, called A-, B-, C-, and D-cells may be differentiated. The A- and B-cells produce different kinds of material; they are not thought to be stages in a secretory cycle. The C- and D-cells are probably not neurosecretory. The corpora cardiaca are divided into two regions. One part stores neurosecretory material from the pars intercerebralis and the other is glandular in appearance. Material discharged from the A- and B-cells in the immature female passes along the nervi corporis cardiaci I to the anterior parts of the corpora cardiaca. The mature female is characterized by the presence of very much larger amounts of material in the corpora cardiaca, in the nervi corporis cardiaci I, and in the A-cells of the pars intercerebralis. The significance of this larger amount of material with respect to neurosecretory cell activity is discussed.

Menshikovite Pd3Ni2As3 and associated minerals of sulphide ores within the Eastern flank of the Oktyabrsky deposit (Norilsk ore field)

2020 ◽  
pp. 22-29
Author(s):  
E. M. Spiridonov ◽  
S. N. Belyakov ◽  
N. N. Korotayeva ◽  
K. V. Egorov ◽  
Yu. A. Ivanova ◽  
...  
Keyword(s):  
Noble Metals ◽  
Precious Metals ◽  
Theoretical Data ◽  
Silicate Matrix ◽  
Average Composition ◽  
Eastern Flank ◽  
Sulphide Ores ◽  
Increased Activity ◽  
Low Activity ◽  
Talnakh Deposit

Significant amount of menshikovite (rare palladium and nickel arsenide) Pd3Ni2As3 was found on the Eastern flank of the Oktyabrsky deposit (Norilsk ore field), near the contact of solid and impregnation sulfide Co-Ni-Cu ores among magnetite-plagioclase-fassaite skarns. Sulfide material of both ores consists of chalcopyrite, pentlandite, pyrrhotite and cubanite aggregates, which are the products of subsolidus transformations of high-temperature solid solutions Iss3, Iss4 and subordinate Mss; with interpositions of later Se-galenite. Menshikovite in association with mertieite-II, silver-gold (fineness 756–706), golden-electrum (fineness 694–672), kotulskite, moncheite, rare altaite, hessite, naldrettite and melonite forms small (up to 30 microns) metasomatic growths on the contact of silicate matrix and magmatogenic sulfide aggregates. The average composition of menshikovite is close to theoretical data: (Pd2,98Ru0,03)3,01(Ni1,89Fe0,-08Co0,01)1,98 (As2,94Se0,04Bi0,02Sn0,01)3,01. Sperrylite metacrystals cut the borders of menshikovite accretions as well as other minerals of precious metals and contain “corroded” inclusions. This association of minerals of noble metals has arisen under the increased activity of As, Te, Sb, Bi and low activity of Sn in fluids. Menshikovite is typical for Pd-rich ores of the Oktyabrsky Deposit, while mayakite PdNiAs (another palladium and nickel arsenide) is relatively widely developed in ores of the Talnakh Deposit (Mayak mine and partly Komsomolsky mine) and the Norilsk-I. Perhaps, such a distribution of palladium-nickel arsenides is an element of mineral zonality of the Norilsk ore field.

scholarly journals Resolution of myocardial phospholipase C into several forms with distinct properties

1983 ◽  
Vol 215 (2) ◽  
pp. 325-334 ◽  
Author(s):  
M G Low ◽  
W B Weglicki
Keyword(s):  
Ion Exchange ◽  
Phospholipase C ◽  
Gel Filtration ◽  
Maximal Activity ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Elution Profile ◽  
Close Correspondence ◽  
Molecular Weights ◽  
Low Activity

Phospholipase C activity capable of hydrolysing phosphatidylinositol in bovine heart was resolved into four forms (I-IV) by ion-exchange chromatography. Some of these forms could only be detected if the assay was performed at acidic pH (I and IV) or in the presence of deoxycholate (II). Gel-filtration chromatography indicated that the four forms had different molecular weights in the range 40000-120000. I, II and III all had pH optima in the range 4.5-5.5. However, the major form (III) also had substantial activity at pH 7.0 and above. The activities of I, II and III at pH 7.0 were stimulated by deoxycholate; this effect was most marked with I and II, which had very low activity at this pH. All forms of the enzyme were inhibited by EGTA and required 2-5 mM-CaCl2 for maximal activity. When the fractions eluted from the ion-exchange and gel-filtration columns were assayed with polyphosphoinositides as substrates there was a close correspondence to the elution profile obtained with phosphatidylinositol as substrate; there was no evidence for the existence in heart of phospholipase C activities specific for individual phosphoinositides.

Explanations Pertaining to the Hip Joint Flexor Moment During the Stance Phase of Human Walking

2012 ◽  
Vol 28 (5) ◽  
pp. 542-550 ◽  
Author(s):  
Erik B. Simonsen ◽  
Katrine L. Cappelen ◽  
Ragnhild í Skorini ◽  
Peter K. Larsen ◽  
Tine Alkjær ◽  
...  
Keyword(s):  
Hip Joint ◽  
Stance Phase ◽  
Activity Level ◽  
Upper Body ◽  
Weak Activity ◽  
Hip Flexor ◽  
Male Subjects ◽  
Increased Activity ◽  
Low Activity ◽  
Iliacus Muscle

A hip joint flexor moment in the last half of the stance phase during walking has repeatedly been reported. However, the purpose of this moment remains uncertain and it is unknown how it is generated. Nine male subjects were instructed to walk at 4.5 km/h with their upper body in three different positions: normal, inclined and reclined. Net joint moments were calculated about the hip, knee and ankle joint. The peak hip joint flexor moment during late stance was significantly lower during inclined walking than in the two other conditions. During normal walking the iliacus muscle showed no or very weak activity and first at the transition from stance to swing. When walking reclined, a clear but rather low activity level of the iliacus muscle was seen in the first half of the stance phase, which could contribute to the hip moment. In the inclined condition the iliacus showed much increased activity but only in the swing phase. It is concluded that the hip flexor moment in question is largely generated by passive structures in the form of ligaments resisting hip joint extension.

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