EFFECTS OF ADRENALECTOMY AND/OR DEFICIENCY OF PITUITARY PROLACTIN SECRETION ON INITIATION AND MAINTENANCE OF LACTATION IN MICE

1973 ◽  
Vol 58 (1) ◽  
pp. 67-73 ◽  
Author(s):  
HIROSHI NAGASAWA ◽  
REIKO YANAI
Keyword(s):  
Nucleic Acid ◽  
Potent Inhibitor ◽  
Prolactin Secretion ◽  
Nucleic Acid Content ◽  
Maternal Behaviour ◽  
Dna And Rna ◽  
Body Weights ◽  
Pituitary Prolactin ◽  
Duration Of Pregnancy ◽  
Average Body

SUMMARY In order to examine the effects of deficiency of adrenal corticosteroids and/or prolactin on the initiation and maintenance of lactation in mice, C3H/He female mice were adrenalectomized and/or implanted during days 13–15 of pregnancy with a pellet of 2-bromo-α-ergocryptine (EC), a potent inhibitor of pituitary prolactin secretion. Average body weights of the young and mammary contents of DNA and RNA were determined on days 0 (day of parturition) and 10 of lactation. On day 0, no differences in these parameters were found among groups, and plenty of milk was present in the stomachs of the young. Furthermore, the treatments did not affect the duration of pregnancy, the number of still-born young or the maternal behaviour at parturition. All young in the group adrenalectomized and implanted with EC died by day 2. Adrenalectomy or implantation of EC retarded the growth of young after day 2 and decreased markedly the mammary nucleic acid content on day 10. These results strongly suggest that adrenal corticosteroids and prolactin play minor roles in the initiation of lactation at parturition, while they are indispensable for the maintenance of lactation in mice.

MAMMARY NUCLEIC ACIDS AND PITUITARY PROLACTIN SECRETION DURING PROLONGED LACTATION IN MICE

1976 ◽  
Vol 70 (3) ◽  
pp. 389-395 ◽  
Author(s):  
H. NAGASAWA ◽  
R. YANAI
Keyword(s):  
Mammary Gland ◽  
Dna Content ◽  
Rna Synthesis ◽  
Prolactin Secretion ◽  
Nucleic Acid Content ◽  
Plasma Prolactin ◽  
Litter Weight ◽  
Dna And Rna ◽  
Pituitary Prolactin

SUMMARY Lactation was prolonged until 61 days by repeated renewal of litters every week after day 12 in primiparous C3H/He strain mice. On days 12, 19, 40 and 61 of lactation, litters were removed for 5 h and after 1 h of resuckling the synthesis of DNA and RNA in the mammary gland was estimated by the incorporation of [3H]thymidine and [14C]uridine into mammary DNA and RNA in vitro respectively. Mammary nucleic acid content and pituitary and plasma levels of prolactin were also assayed. Nulliparous mice were similarly treated on day 19 of pregnancy. The percentage gain in litter weight per week was highest between days 5 and 12 of lactation, declined until days 26–33 and became steady thereafter. Mammary DNA synthesis was extremely high on day 19 of pregnancy, decreased on day 12 of lactation to less than one-fifteenth of that on day 19 of pregnancy and increased linearly thereafter. Changes in mammary DNA content were not so marked, but DNA content was high on days 12 and 19 of lactation. RNA synthesis was highest on day 19 of pregnancy, abruptly decreased on days 12 and 19 of lactation and increased again with the advance of lactation. Mammary RNA content, RNA:DNA and 14C:3H ratios increased from day 19 of pregnancy to days 12–19 of lactation and decreased on days 40 and 61. While the pituitary levels of prolactin were almost constant during lactation, they were significantly higher than those on day 19 of pregnancy. There were only slight differences in plasma prolactin levels at any stage.

MAMMARY GROWTH AND FUNCTION AND PITUITARY PROLACTIN SECRETION IN FEMALE NUDE MICE

1977 ◽  
Vol 86 (4) ◽  
pp. 794-802 ◽  
Author(s):  
Hiroshi Nagasawa ◽  
Reiko Yanai
Keyword(s):  
Nude Mice ◽  
Plasma Levels ◽  
Growth Stimulation ◽  
Prolactin Secretion ◽  
The Other ◽  
Dna And Rna ◽  
Female Nude ◽  
Structural Growth ◽  
And Function ◽  
Pituitary Prolactin

ABSTRACT Mammary structural growth in the wholemount preparation, content and synthesis of mammary DNA and RNA estimated by the incorporation of [3H]thymidine and [14C]uridine, pituitary and plasma levels of prolactin and weights and histological structures of some organs of female nude mice (nu/nu) were compared to those of the control (nu/+) with the same genetical background (BALB/c). Both at 3 months of age and on day 1 of lactation, the weights per 100 g body weight of adrenals, spleen and liver of nu/nu mice were significantly higher than those of nu/+ mice. Mammary growth stimulation by pituitary graft was much more marked in nu/nu mice than in nu/+ mice. Slight differences between groups were found in the pituitary and plasma levels of prolactin, in the histological structures of ovaries as well as of the adrenals and thyroids and in the pattern of oestrous cycles. On the other hand, the content and synthesis of mammary DNA at 3 months of age and content and synthesis of both DNA and RNA and RNA/DNA ratio on day 1 of lactation were significantly higher in nu/+ mice than in nu/nu mice. All findings suggest that thymus deficient immunosuppression has deleterious effects on mammary growth and function without its alteration in the secretion of prolactin and oestrogen and probably through its decrease in mammary responsiveness to mammotrophins.

Effects of reproduction in sheep on the rate of cell division and nucleic acid content of the ruminal mucosa

1973 ◽  
Vol 80 (3) ◽  
pp. 443-449 ◽  
Author(s):  
Susan J. Moon ◽  
Rosa M. Campbell
Keyword(s):  
Cell Division ◽  
Nucleic Acid ◽  
Mitotic Index ◽  
Inverse Relationship ◽  
Post Partum ◽  
Nucleic Acid Content ◽  
Dna And Rna ◽  
Ruminal Epithelium ◽  
Total Dna ◽  
And Control

SummaryThe weight of the ruminal mucosa of breeding Blackface ewes and its total DNA and RNA content rose after parturition to reach a peak at 45 days post partum. There were no constant significant changes with time in the concentration of the nucleic acids.It was found that there was a positive correlation between the amount of food eaten during the final week of life and the weight of the ruminal mucosa and the length of ruminal papillae. The mitotic index of the ruminal epithelial cells was very variable but most of the higher values occurred between 7 and 80 days post partum. The mitotic index could not be correlated with the amount of food eaten in the week before slaughter, but high values were not recorded when the food intake of lactating ewes was restricted to that of non-breeding controls. It is suggested that the most likely explanation for these findings is that in the ruminal epithelium of lactating ewes fed to appetite, oell division occurred in waves or bursts.Hyperkeratosis of the ruminal epithelium occurred in pregnant and control animals but regressed during lactation and reappeared in the post-weaning period. The inverse relationship between the hyperkeratosis and the rate of cell division is of great interest when considering the aetiology of ruminal disease.

Influence of the RNA content on oogenesis in the bobbed mutants of Drosophila melanogaster

Development ◽  
1971 ◽  
Vol 25 (2) ◽  
pp. 237-246
Author(s):  
Jag Mohan
Keyword(s):  
Drosophila Melanogaster ◽  
Nucleic Acid ◽  
Acid Content ◽  
Nucleic Acid Content ◽  
Wild Type ◽  
Dna And Rna ◽  
Stage Of Development ◽  
Rna Content ◽  
Egg Chambers ◽  
Total Dna

Developing egg chambers of Drosophila melanogaster (wild-type and bobbed mutants) have been examined for their nucleic acid content by cytophotometric methods. No differences were observed in the total DNA and RNA content of the egg chambers at all stages between the bobbed mutants and the wild type. It is shown that the process of oogenesis in bobbed females is prolonged, and that this prolongation occurs at all the stages of oocyte development. Since the ovaries of the bobbed females synthesize less rRNA per unit time, it is likely that this prolongation allows the egg chambers of the bobbed females to normalize their RNA content. When they achieve a given RNA content, they proceed to the next stage of development.

scholarly journals The Senescence-Associated Endonuclease, PhENDO1, Is Upregulated by Ethylene and Phosphorus Deficiency in Petunia

Horticulturae ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 46
Author(s):  
Michelle L. Jones ◽  
Shuangyi Bai ◽  
Yiyun Lin ◽  
Laura J. Chapin
Keyword(s):  
Nucleic Acid ◽  
Petunia Hybrida ◽  
Phosphorus Deficiency ◽  
Peptide Sequence ◽  
Flower Senescence ◽  
Nucleic Acid Content ◽  
Virus Induced Gene Silencing ◽  
Dna And Rna ◽  
Endogenous Expression ◽  
N Starvation

The upregulation of endonuclease activities and subsequent decreases in the nucleic acid content of leaves and petals are characteristics of senescence that allow for nutrient remobilization from dying organs. We previously identified a 43-kDa endonuclease activity (PhNUC1) that was upregulated in Petunia × hybrida petals during senescence. PhNUC1 has optimal activity at neutral pH, is enhanced by Co2+, and degrades both DNA and RNA. The peptide sequence of a 43-kDa endonuclease identified from senescing petals by 2-dimensional gel electrophoresis was used to clone the gene (PhENDO1) encoding the senescence-associated protein. PhENDO1 expression was upregulated in petals during the senescence of unpollinated and pollinated flowers and by ethylene treatment. When petunias were grown under nutrient deficient conditions, P-starvation, and to a lesser extent N-starvation, induced expression of PhENDO1. The endogenous expression of PhENDO1 was down regulated using virus induced gene silencing (VIGS), and in-gel endonuclease assays confirmed that the activity of the 43-kDa PhNUC1 was decreased in senescing corollas from PhENDO1-silenced (pTRV2:PhCHS:PhENDO1) plants compared to controls (pTRV2:PhCHS). Down regulating PhENDO1 in petunias did not alter flower longevity. While PhENDO1 may be involved in nucleic acid catabolism during senescence, down regulating this gene using VIGS was not sufficient to delay flower senescence.

scholarly journals Ameliorating effects of Vit-C on protein and nucleic acid content in dimecron intoxicated chick embryos

2016 ◽  
Vol 2 ◽  
pp. 20-27
Author(s):  
Biplab Kumar Behera ◽  
Keyword(s):  
Nucleic Acid ◽  
Toxic Effect ◽  
Quantitative Study ◽  
Acid Content ◽  
Nucleic Acid Content ◽  
Chick Embryos ◽  
Dna And Rna ◽  
Hen’S Egg ◽  
Made In ◽  
Vit C

Dimecron when introduced into the fertilized hen’s egg at a certain dose before incubation shows a characteristic and interesting feature which has been studied and discussed. A quantitative study of proteins from different organs viz. liver, kidney and brain has been made in the present study. A significant reduction in the quantity of the protein of all the organs is observed. The study witnessed the activity of DNA and RNA that undergoes a decline in its quantity by the action of the pesticide. The toxic effect of pesticides is recovered by the use of ameliorating agent like Vit C. Keywords: Atropine, DNA, organophosphate, protein, RNA, Vit-C.

scholarly journals THE RIBONUCLEIC ACID AND DEOXYRIBONUCLEIC ACID CONTENT OF MONONUCLEAR LEUKOCYTES OF DIFFERENT SIZES STUDIED BY ULTRAVIOLET CYTOPHOTOMETRY

1973 ◽  
Vol 21 (7) ◽  
pp. 628-633 ◽  
Author(s):  
ALFREDO MARIANO GARCIA ◽  
PATRICIA A. N. SULLIVAN
Keyword(s):  
Nucleic Acid ◽  
Cell Size ◽  
Dna Content ◽  
Random Error ◽  
Acid Content ◽  
Deoxyribonucleic Acid ◽  
Nucleic Acid Content ◽  
Mononuclear Leukocytes ◽  
Total Nucleic Acid ◽  
Dna And Rna

Rat mononuclears (lymphocytes and monocytes) were studied for total nucleic acid content by means of ultraviolet cytophotometry. Another set was treated with ribonuclease, and deoxyribonucleic acid (DNA) was measured using the same technique. It was found that total nucleic acid content (DNA and RNA) increases linearly with cell size from about 20 units in lymphocytes having 5 µ in diameter up to around 30 units in cells having 12-14 µ in diameter; this is to say, an almost 50% increase for a 6-7-fold enlargement. After ribonuclease treatment, however, the value of the integrated extinction (DNA) tends to remain constant for different cell sizes. A 650% variation in area is accompanied by a DNA change of less than 6%. The differences between treated and nontreated cells are nonsignificant for populations having up to 7.0-7.5 µ in diameter, which implies that small lymphocytes either have a negligible amount of RNA or that the instrument is not sensitive enough to detect it (less than 7% of the DNA content, this figure being the random error of our technique). These differences become highly significant for mononuclears having 8 µ or more in diameter. Therefore, while DNA tends to be constant and independent from cell size, RNA content tends to be harmoniously inconstant, since it is correlated with cell (and nuclear) size and degree of chromatin diffusion.

Changes in DNA and RNA in the rat adenohypophysis following bilateral adrenalectomy, sham adrenalectomy, and the chronic injection of cortisol

1968 ◽  
Vol 46 (3) ◽  
pp. 431-439 ◽  
Author(s):  
Jacob Kraicer ◽  
Su Chiau Cheng
Keyword(s):  
Nucleic Acid ◽  
Feedback Control ◽  
Acid Content ◽  
Transient Increase ◽  
Bilateral Adrenalectomy ◽  
Nucleic Acid Content ◽  
Dna And Rna ◽  
Rna Content ◽  
Chronic Injection

Changes in adenohypophyseal DNA and RNA content were determined as a function of time following adrenalectomy, sham adrenalectomy, and the chronic injection of cortisol. The stess of operation resulted in a transient increase in adenohypophyseal nucleic acid content, whereas the increase in secretion of ACTH induced by feedback control did not. An attempt is made to correlate the changes in nucleic acid content with the concurrent changes in the intensity of biosynthesis of ACTH.

EFFECTS OF ADMINISTERING ANTISERA TO MOUSE GROWTH HORMONE AND PROLACTIN ON GAIN IN LITTER WEIGHT AND ON MAMMARY NUCLEIC ACID CONTENT OF LACTATING C3H MICE

1972 ◽  
Vol 55 (1) ◽  
pp. 31-NP ◽  
Author(s):  
Y. N. SINHA ◽  
U. J. LEWIS ◽  
W. P. VANDERLAAN
Keyword(s):  
Growth Hormone ◽  
Body Weight ◽  
Nucleic Acid ◽  
Acid Content ◽  
Nucleic Acid Content ◽  
Ovarian Weight ◽  
Litter Weight ◽  
Dna And Rna ◽  
Lactating Mothers ◽  
C3h Mice

SUMMARY The effects of administering antiserum to mouse growth hormone (GH) and prolactin on lactation and mammary nucleic acid content of C3H mice were studied. Injections of either antisera to lactating mothers suppressed the gain in body weight of their suckling young, GH antiserum more readily than prolactin antiserum. A combined injection of the two antisera resulted in an immediate retardation of the gain in body weight of the young. Although both antisera reduced DNA and RNA content of the mammary gland, GH antiserum appeared to affect DNA content predominantly whereas prolactin antiserum affected RNA: DNA ratio, suggesting involvement of GH primarily in cell proliferation and of prolactin in protein synthesis. Both antisera abolished the gain in maternal body weight. Mouse GH antiserum decreased maternal adrenal weight whereas both antisera reduced ovarian weight. The results suggest that both GH and prolactin may be involved in normal lactation and in maintenance of body weight in C3H mice.

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