The developmental endocrinology of the spleen in chick embryos

Development ◽  
1970 ◽  
Vol 24 (2) ◽  
pp. 357-365
Author(s):  
T. W. Betz
Keyword(s):  
Chick Embryo ◽  
Growth And Development ◽  
White Pulp ◽  
Chick Embryos ◽  
Pars Distalis ◽  
Liver Growth ◽  
Body Weights ◽  
Pars Nervosa ◽  
Splenic White Pulp ◽  
Red Pulp

Partial decapitation (‘hypophysectomy’) of the chick embryo significantly reduces body growth by 20 days (stage 46 −) of incubation as indicated by body weights, 60% of normal; the lengths of the toe and tibiotarsus, 80% and 78% of normal respectively; and liver growth, 47% of normal, but the gall bladder was not apparently enlarged. It significantly increases spleen growth to 82 % greater than normal, suppresses or retards white pulp differentiation and splenic vasculogenesis but enhances red pulp development. A single pars distalis gland placed as a chorioallantoic graft into operated embryos prevents the development of these defects except for liver growth which, while improved, is still subnormal. If the number of grafts is increased by one or two there is no change in the amount of influence on growth and development of the chick embryo. This apparent regulation occurs by some unknown mechanism even in the absence of the hypothalamus. Thus body and liver growth is normally stimulated by the pars distalis but spleen growth and red pulp differentiation are suppressed even though the gland stimulates splenic white pulp histogenesis. The hypothalamus, epiphysis and pars nervosa (removed by partial decapitation) are not apparently involved in the developmental endocrinology of the spleen in chick embryos.

The developmental endocrinology of the spleen in chicken embryos

Development ◽  
1973 ◽  
Vol 29 (1) ◽  
pp. 245-251
Author(s):  
R. B. Goldberg ◽  
T. W. Betz
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
White Pulp ◽  
Spleen Size ◽  
Pars Distalis ◽  
Chicken Embryos ◽  
Hormone Levels ◽  
Red Pulp

Pars distalis-extract treatment of intact or ‘hypophysectomized’ chicken embryos resulted in a splenomegaly, perhaps of a host-versus-graft nature, by 17 and 17·5 days of incubation. Pars distalis grafts in intact embryos reduced spleen size, encouraged white-pulp follicle formation, but ‘suppressed’ red-pulp development. Adult spleen extract and bovine serum albumin did not change spleen sizes or histology appreciably in intact embryos. Perhaps pars distalis hormones inhibit red-pulp development or stimulate white-pulp follicles which may compete with red-pulp proliferation but encourage splenic vasculogenesis alone or by stimulating adrenocorticoid, thyroid, and other hormone levels while other extract factors cause splenomegaly.

scholarly journals Studies on Regeneration of Heterotopic Splenic Autotransplants

Blood ◽  
1973 ◽  
Vol 41 (5) ◽  
pp. 701-709 ◽  
Author(s):  
Mehdi Tavassoli ◽  
R. Judith Ratzan ◽  
William H. Crosby
Keyword(s):  
Blood Cells ◽  
Subcutaneous Tissue ◽  
Regenerative Process ◽  
Splenic Tissue ◽  
White Pulp ◽  
Microscopic Structure ◽  
Small Arteries ◽  
Splenic White Pulp ◽  
Splenic Red Pulp ◽  
Red Pulp

Abstract Fragments of spleen autotransplanted to subcutaneous tissue of the abdomen in the rat undergo almost complete necrosis and then regenerate into splenic tissue with a microscopic structure indistinguishable from the structure of the original organ. The regenerative process reminiscent of the spleen’s embryogenesis, originates from a shell of surviving splenic tissue at the surface of the implant. The regenerative zone first consists of almost monotonous connective tissue cells interspersed with red blood cells; it develops into splenic red pulp consisting of sinuses and intersinal cords. As capillaries develop, the structure of small arteries and peri-arterial lymphatic sheaths appear, and soon the structure of splenic white pulp becomes evident. Some 5 wk after autotransplantation, the splenic reconstruction is complete. The weight of the recovered tissue is a linear function of the weight of the implanted tissue; yet the linearity is lost when the weight of the implanted tissue exceeds 100 mg.

scholarly journals The Action of Phytohemagglutinin in Rabbits. V. Morphological Changes Following Previous Immunization with and Daily Injections of Phytohemagglutinin

Blood ◽  
1969 ◽  
Vol 33 (5) ◽  
pp. 727-738
Author(s):  
J. B. BLENNERHASSETT ◽  
C. K. NASPITZ ◽  
M. RICHTER
Keyword(s):  
Chemotherapeutic Agent ◽  
Single Injection ◽  
Morphological Changes ◽  
White Pulp ◽  
Myeloid Metaplasia ◽  
Splenic White Pulp ◽  
Circulating Antibodies ◽  
Splenic Red Pulp ◽  
Morphologic Changes ◽  
Red Pulp

Abstract The administration of a series of four or eight daily injections of PHA neither diminished nor enhanced the peripheral and parenchymal changes observed after a single injection of PHA. These changes include the peripheral leukopenia followed by a leukocytosis, the hyperplasia of the splenic white pulp, and the myeloid metaplasia or infiltration in the splenic red pulp. The circulating leukocytes appear to become resistant to the leukopenic action of PHA following a series of injections of PHA. However, this stage of refractoriness lasts only one to two weeks in the absence of any further injection of PHA. Immunization with PHA with formation of antibodies capable of neutralizing the mitogenic factor(s) in PHA did not affect the capacity of a subsequent challenge injection of PHA to induce the characteristic morphologic changes which follow a single injection of PHA. Thus, the presence of circulating antibodies does not invalidate the use of PHA as a chemotherapeutic agent.

scholarly journals Effect of exposure to different light colors on embryonic development and neurophysiological traits in the chick embryo

2021 ◽  
pp. 1284-1289
Author(s):  
S. M. Abdulateef ◽  
M. A. Al-Bayar ◽  
A. A. Majid ◽  
S. S. Shawkat ◽  
A. Tatar ◽  
...  
Keyword(s):  
Body Weight ◽  
Chick Embryo ◽  
Environmental Factors ◽  
Embryonic Development ◽  
Growth And Development ◽  
Red Light ◽  
Green Light ◽  
Chick Embryos ◽  
Broiler Chick ◽  
The Impact

Background and Aim: Many environmental factors exist that influence embryonic development which is missing in the poultry industry, such as light in incubation facilities or hatcheries. Light plays an important role in the growth and development of chick embryos, whereas dark environments can lead to hatching failure or embryo distortion. Therefore, this study aimed to demonstrate the importance of light and its various colors on the growth and development of broiler chick embryos. Materials and Methods: Four treatments were used to study the impact of various light colors on the growth of embryos and their neurophysiological traits: Dark without light (D), red light (RL), blue light (BL), and green light (GL), with three replicates per treatment (25 eggs/replicate) for a total of 300 fertile Ross 308 eggs. Each treatment was assigned to one incubator (75 eggs/incubator), whereas all other conditions were kept the same. Results: The results showed a significant increase (p<0.01) in embryonic development for embryo weight, chick body weight, hatchability, and embryo index for RL, BL, and especially GL. RL, BL, and especially GL significantly increased (p<0.01) neurophysiological traits of the neurons, brain weight, and brain index. Conclusion: The use of light during the embryonic period affects the development of the embryo and its neurophysiological traits.

The effect of early thymectomy on histogenesis of the lymphoid organs in Xenopus laevis

Development ◽  
1971 ◽  
Vol 26 (2) ◽  
pp. 219-229
Author(s):  
Margaret J. Manning
Keyword(s):  
Xenopus Laevis ◽  
Lymphoid Organs ◽  
White Pulp ◽  
Normal Complement ◽  
Splenic White Pulp ◽  
The Difference ◽  
Immature Cells ◽  
Splenic Red Pulp ◽  
Red Pulp

The role of the thymus in the ontogenetic development of the lymphoid system of the clawed toad, Xenopus laevis, was investigated by removing the organ at stage 49 of Nieuwkoop & Faber (1967), a stage when small lymphocytes are present in the thymus but have not yet appeared in the peripheral lymphoid organs. Complete thymectomy, confirmed histologically, was achieved in nine larvae killed at stage 56 and in 23 larvae killed at stage 59. The spleen was smaller in thymectomized larvae than in sham-thymectomized controls in the series killed at stage 56, but the difference was no longer significant at stage 59. In both series, thymectomized larvae showed a fall in the number of extra-follicular lymphocytes and an increase in the reticulo-myeloid elements of the splenic red pulp. The pharyngeal ventral cavity bodies were moderately or severely depleted of lymphocytes. In other areas, histogenesis proceeded normally in the absence of the thymus. In the splenic white pulp, the follicles, which comprised immature cells of the lymphoblast type at the time of thymectomy, developed their normal complement of lymphocytes. All larvae grew and developed at the normal rate.

Growth and development of the barren-ground caribou. II. Postnatal growth rates

1968 ◽  
Vol 46 (5) ◽  
pp. 1023-1029 ◽  
Author(s):  
E. H. McEwan
Keyword(s):  
Growth And Development ◽  
Growth Characteristic ◽  
Growth Curves ◽  
Postnatal Growth ◽  
Maintenance Costs ◽  
Cyclical Pattern ◽  
Body Weights ◽  
In Captivity ◽  
Growth Constants ◽  
Slow Growing

The growth curves of minimum body weights of fast-growing caribou reared in captivity and slow-growing wild caribou are compared. Captive animals exhibit a cyclical pattern of growth characteristic of other cervid species. The differences in the declining growth constants of wild caribou compared to captive caribou are attributed to environmental factors and activity, resulting in higher maintenance costs.

scholarly journals Ascorbic acid biosynthesis: a precursor study on plants

2004 ◽  
Vol 16 (3) ◽  
pp. 147-154 ◽  
Author(s):  
Anderson D. Barata-Soares ◽  
Maria Luiza P. A. Gomez ◽  
Carlos Henrique de Mesquita ◽  
Franco M. Lajolo
Keyword(s):  
Ascorbic Acid ◽  
Sweet Pepper ◽  
The Other ◽  
White Pulp ◽  
Acid Biosynthesis ◽  
Ripe Fruit ◽  
Ripening Stages ◽  
Main Pathway ◽  
Ascorbic Acid Biosynthesis ◽  
Red Pulp

Since the first isolation of ascorbic acid (AsA) in 1928, few papers have been published regarding the biosynthesis of AsA in plants, especially in fruits. It took as long as 1998, before Wheeler, Jones and Smirnoff, based on a study with Arabidopsis leaves, proposed what can be considered the main pathway of biosynthesis of AsA, in which L-galactose (L-GAL) is a key precursor. This paper reports the effectiveness of some precursors (cold or radiolabeled) in the biosynthesis of AsA in different plants: green sweet pepper, white-pulp guava, red-pulp guava, papaya and strawberry at two ripening stages (mature green and ripe for papaya and mature green and half red for strawberry) and broccoli. The 'Smirnoff-Wheeler' pathway was functioning and active in all sources studied, as demonstrated by the increase in AsA contents and incorporation of labeled precursors into AsA. In papaya, the AsA content in the ripe fruit was higher than in the mature green, indicating the synthesis of AsA during ripening. On the other hand, the AsA content in the mature green strawberry was similar to that of the half red fruits. Our data demonstrate that L-GAL and L-Galactono-1,4-lactone (L-GL) are effective precursors for the biosynthesis of AsA in fruits and also provided additional evidence for the participation of D-mannose (D-MAN) and D-glucose-1P in the biosynthesis of AsA in plants.

scholarly journals Morphometric and Histopathologic Analysis of Lymphoid Depletion in Murine Spleens Following Infection with Brucella abortus strains 2308 or RB51 or an htrA Deletion Mutant

1996 ◽  
Vol 33 (3) ◽  
pp. 282-289 ◽  
Author(s):  
M. V. Palmer ◽  
N. F. Cheville ◽  
F. M. Tatum
Keyword(s):  
Morphometric Analysis ◽  
Brucella Abortus ◽  
Marginal Zone ◽  
White Pulp ◽  
Splenic White Pulp ◽  
Lymphoid Depletion ◽  
Histopathologic Changes ◽  
Histopathologic Analysis ◽  
Marginal Zones

BALB/C mice were inoculated intraperitoneally with suspensions of Brucella abortus strains 2308 or RB51 or an htrA mutant. Spleens were examined on postinoculation day (PID) 2, 4, 7, 10, 15, 21, 30, and 60. Brucellae were cultured in high numbers from the spleens of mice infected with strains 2308 or htrA through PID 60; however, mice infected with strain RB51 cleared the infection between PID 30 and PID 60. Histopathologic changes in spleens from 2308-infected mice were characterized by marked accumulations of macrophages, which expanded marginal zones beginning as early as PID 7 and persisting through PID 60. Morphometric analysis showed a decrease in splenic white pulp in 2308-infected mice at PID 10, which correlated with the peak of bacterial infection. Although this decrease was significant ( P < 0.05) when compared with values at the previous (PID 7) and the following (PID 15) time periods, it was not significantly different from white pulp values noted at PID 2 or PID 4 or the values for control spleens. Spleens from RB51-infected mice showed only mild to moderate accumulations of macrophages in marginal zone areas during the peak of RB51 infection (PID 7-10). Morphometric analysis of RB51-infected spleens showed a decrease in white pulp area, which coincided with peak bacterial numbers. However, this decrease was not significant ( P > 0.05). Spleens from mice infected with the htrA mutant showed moderate to marked accumulations of macrophages in marginal zone areas, which persisted through PID 60. Multifocal necrosis in lymphoid follicles as early as PID 4 was seen in both htrA and 2308 infection. Morphometric analysis of htrA-infected spleens revealed no significant decrease in white pulp and no obvious correlation with bacterial numbers in the spleen. These results suggest that virulent B. abortus does not induce lymphoid depletion significantly below those values seen in noninfected mice; thus, the possible role of lymphoid depletion in the pathogenesis of brucellosis remains questionable.

Sign in / Sign up

Export Citation Format

Share Document