Factors Influencing Diuresis in Rats Following Total-Body X-Irradiation

1957 ◽  
Vol 189 (1) ◽  
pp. 11-14 ◽  
Author(s):  
E. Irene Pentz ◽  
Robert J. Hasterlik
Keyword(s):  
Adrenal Cortex ◽  
Anterior Pituitary ◽  
Adrenal Glands ◽  
Anterior Lobe ◽  
Posterior Pituitary ◽  
Cortical Control ◽  
Factors Influencing ◽  
X Irradiation ◽  
Diuretic Response ◽  
Total Body

An immediate diuresis has been observed in rats exposed to total-body x-irradiation ranging between 100 and 400 r. Since the highest dosage produced more consistent results, it was used in conjunction with extirpation of various glands and other organs in an effort to determine the mechanism that responds so promptly to x-irradiation. The anterior pituitary and the adrenal cortex are of prime importance in this reaction. Removal of the anterior lobe of the pituitary or removal of the adrenal glands is sufficient to completely inhibit diuresis following 400 r x-irradiation. This diuretic response is not dependent upon the presence of the posterior pituitary since animals having only this gland removed became diuretic following exposure to 400 r. The evidence suggests that the release of antidiuretic substances from tissues other than the posterior pituitary is under anterior pituitary-adrenal cortical control.

scholarly journals Vascular endothelial growth factor in the rat pituitary: differential distribution and regulation by estrogen

2000 ◽  
Vol 165 (2) ◽  
pp. 483-492 ◽  
Author(s):  
AL Ochoa ◽  
NA Mitchner ◽  
CD Paynter ◽  
RE Morris ◽  
N Ben-Jonathan
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Anterior Pituitary ◽  
Anterior Lobe ◽  
Intermediate Lobe ◽  
Vascular Endothelial ◽  
Posterior Pituitary ◽  
Vegf Expression ◽  
Neural Lobe ◽  
Endothelial Growth Factor

Vascular endothelial growth factor (VEGF), an endothelial cell mitogen and permeability factor, participates in tumor angiogenesis, but less is known about its regulation or function in normal vascular homeostasis. In the uterus, which undergoes cyclic changes in its vasculature, VEGF is induced by estrogen. Since the pituitary gland contains highly permeable capillaries and is estrogen-responsive, our objectives were to localize VEGF expression within the pituitary and to determine whether it is regulated by estrogen in both the pituitary and the somatolactotrope cell line, GH(3). Ovariectomized rats were injected with estradiol, and pituitaries and uteri were subjected to in situ hybridization or quantitative reverse transcription-polymerase chain reaction (RT-PCR). VEGF expression was strong and punctate in the neural lobe, weaker and diffuse in the anterior lobe and undetectable in the intermediate lobe. Two VEGF isoforms, 164 and 120, were detected in all tissues. In the posterior pituitary, VEGF expression was 3- to 6-fold higher than in the anterior pituitary or uterus and was unaltered by estrogen. In contrast, anterior pituitary VEGF was induced by estrogen within 1 h, peaked at 3 h, and returned to basal levels by 24 h. Similar dynamics, albeit 10-fold higher, were seen in the uterus. Translated VEGF proteins were detected by Western blot in both the anterior pituitary and uterus. GH(3) cells also showed a dose- and time-dependent induction of VEGF expression by estrogen. In conclusion: (1) VEGF expression is higher in the neural lobe than in the anterior lobe and is undetectable in the intermediate lobe, (2) the expression of VEGF164 and VEGF120 is rapidly upregulated by estrogen in the anterior pituitary but is unchanged in the posterior pituitary, and (3) the pituitary lactotrope cell line, GH(3), also increases VEGF expression in response to estradiol.

scholarly journals THE EFFECT OF ADRENAL CORTEX AND ANTERIOR PITUITARY EXTRACTS AND INSULIN ON THE HEXOKINASE REACTION

1947 ◽  
Vol 168 (2) ◽  
pp. 583-596
Author(s):  
Sidney P. Colowick ◽  
Gerty T. Cori ◽  
Milton W. Slein
Keyword(s):  
Adrenal Cortex ◽  
Anterior Pituitary

Effect of Total Body X-Irradiation on the Respiration of the Homogenized Duodenal Mucosa of the Rat

Nature ◽  
1957 ◽  
Vol 179 (4549) ◽  
pp. 51-51 ◽  
Author(s):  
S. SZŐNYI ◽  
W. VÁRTERÉSZ
Keyword(s):  
Duodenal Mucosa ◽  
X Irradiation ◽  
Total Body

On the content of prolan in the pituitary gland

1934 ◽  
Vol 30 (6) ◽  
pp. 634-634
Author(s):  
P. Badul
Keyword(s):  
Pituitary Gland ◽  
Histological Examination ◽  
Anterior Lobe ◽  
Posterior Lobe ◽  
Posterior Pituitary ◽  
Posterior Pituitary Lobe

The posterior lobe of the pituitary gland in a bull is free of prolan, while in a human it contains prolan. Only here it can be found in that part of the posterior pituitary lobe adjacent to the anterior lobe. In the bull, too, this part of the pituitary gland is completely free of prolan content. Histological examination shows that in humans, this part of the posterior lobe is crossed by bands of cells from the anterior lobe, which consist exclusively of basophilic cells.

LOCALIZATION AND CHARACTERIZATION OF CHOLINESTERASE IN SUBCELLULAR FRACTIONS OF RAT BRAIN AND BEEF PITUITARY

1961 ◽  
Vol 39 (9) ◽  
pp. 1335-1345 ◽  
Author(s):  
Surendra S. Parmar ◽  
Morley C. Sutter ◽  
Mark Nickerson
Keyword(s):  
Rat Brain ◽  
Cholinesterase Activity ◽  
Succinic Dehydrogenase ◽  
Anterior Lobe ◽  
Subcellular Fractions ◽  
Posterior Pituitary ◽  
Low Concentrations ◽  
Pituitary Glands ◽  
Hydrolysis Of

Fresh rat brains and fresh anterior and posterior pituitary glands of beef were separated by differential centrifugation into subcellular fractions, characterized on the basis of sedimentation and succinic dehydrogenase activity. Cholinesterase activity was measured by both manometric and colorimetric methods, the results of which were comparable. Cholinesterase activity of rat brain was found mainly in the microsome and supernatant fractions. It was quite uniformly distributed in all subcellular fractions of both anterior and posterior pituitary. Comparisons of the relative rates of hydrolysis of acetylthiocholine and butyrylthiocholine, and of inhibition by eserine, indicated that brain contains a much higher percentage of acetylcholinesterase than do both lobes of the pituitary, which contain relatively low concentrations of the specific enzyme. Total cholinesterase activity and its sensitivity to inhibition by eserine in the posterior pituitary were found to be midway between those of the anterior lobe and of the brain, from which the posterior pituitary was derived during embryological development.

THE DEVELOPMENT OF A FEEDBACK MECHANISM BETWEEN THE OVARY AND THE DIENCEPHALIC-HYPOPHYSIAL SYSTEM IN THE RAT

1963 ◽  
Vol 26 (2) ◽  
pp. 287-NP ◽  
Author(s):  
J. PRESL ◽  
J. HORSKÝ ◽  
M. HENZL ◽  
J. JIRÁSEK
Keyword(s):  
Anterior Pituitary ◽  
Anterior Lobe ◽  
Feedback Mechanism ◽  
Histological Structure ◽  
Histological Investigation ◽  
Basic Information ◽  
Ovarian Weight ◽  
The Difference ◽  
Golgi Zone ◽  
Mucoid Cells

SUMMARY With the object of obtaining basic information concerning the establishment of the feedback mechanism between the ovaries and the diencephalic-hypophysial system (DHS), changes in the gonadotrophic activity and histological structure of the anterior pituitary lobe were determined in groups of rats 21 days following ovariectomy on the day of birth or at 5, 10, 15, 20, 30 and 50 days. It was shown that the gonadotrophic activity of the hypophysis of spayed females and non-spayed controls differed using the criterion of uterine weight of the recipient, following ovariectomy at birth. After spaying at the age of 5 days the difference was also statistically significant using the criterion of ovarian weight. Histological investigation showed that in animals ovariectomized at days 1 and 5 there was an increase in PAS-positive mucoid cells in the adenohypophysis with a distinct PAS-positive Golgi zone in the pale centre of the cytoplasm. The results of these experiments show that a feedback mechanism between the ovaries and the DHS becomes established at an age between (21–x) and (26–x) days, where x is the period necessary for the development of demonstrable post-castration changes in the anterior lobe. In view of the reported initiation of ovarian oestrogen production, the hypothesis is discussed that the feedback mechanism begins to function during very early post-natal life.

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