The red blood cells in growing guinea pigs. (Cavia cobaya). II. Communication: erythropoiesis and red blood cells in the postnatal development period

Bone-marrow smears of 175 guinea pigs aged 1-27 days and venous blood samples of 351 animals aged 1-25 days were prepared for cell counting. A significant increase of erythroblasts were found between life day 1 and 2; normoblasts increased in number synchronously with a decrease of erythroblasts after the 5th day. The percentage of the erythroid bone marrow increased from 10 to 14 during the developmental period. Beyond the perinatal period the red blood picture is characterized by the following changes: a decrease of erythrocyte count, hematocrit, hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin; a constant mean corpuscular hemoglobin concentration; an increase of the reticulocyte count. The decrease of the red cell count is compensated by a decreasing oxygen affinity attained by an important increase of 2,3-DPG. Nevertheless, the stimulus for a raising erythropoiesis remains constant which can be shown by the growing percentage of erythroid cells and reticulocytes. The difference between the human postnatal development and that of the guinea pig becomes obvious. Cell counts in dependence of body masses in postnatally growing guinea pigs, veil the perinatal finding of the increase in erythrocytes up to the 5th day and the decrease of the mean corpuscular volume after the 3rd day.     

Dynamics of hematologic parameters and of the erythrocyte deformability index at the juvenal period of rats and guinea pigs

In experiments on Wistar rats and guinea pigs, dynamics of blood hematological parameters and of erythrocyte deformability index (DI) was studied from birth to the 3-month age. In rats, significant changes were revealed in the picture of blood for the first month of postnatal ontogenesis. The number of erythrocytes and leukocytes sharply increased, the number of reticulocytes decreased, their ratio in the degree of maturity was changed. The mean erythrocyte volume and their acidic resistance also decreased. Prior to the 4-week age, DI increased, which was accompanied by an increase in the hemoglobin hydration and flattening of the erythrocyte shape. Then DI decreased and erythrocytes acquired the more spherical shape. After the critical period of 3–4 weeks the studied parameters reached plateau. In guinea pigs, at this period of ontogenesis the hematologic parameters had sufficiently stable values, except for a DI decrease from birth to 1.5 months, then it rose without reaching the initial values. Like in the case with rats, DI had a close correlation with the erythrocyte parameter of shape (O_min).     

Dynamics of hematologic parameters and of the erythrocyte deformability index at the juvenal period of rats and guinea pigs

In experiments on Wistar rats and guinea pigs, dynamics of blood hematological parameters and of erythrocyte deformability index (DI) was studied from birth to the 3-month age. In rats, significant changes were revealed in the picture of blood for the first month of postnatal ontogenesis. The number of erythrocytes and leukocytes sharply increased, the number of reticulocytes decreased, their ratio in the degree of maturity was changed. The mean erythrocyte volume and their acidic resistance also decreased. Prior to the 4-week age, DI increased, which was accompanied by an increase in the hemoglobin hydration and flattening of the erythrocyte shape. Then ID decreased and erythrocytes acquired the more spherical shape. After the critical period of 3-4 weeks the studied parameters reached plateau. In guinea pigs, at this period of ontogenesis the hematologic parameters had sufficiently stable values, except for a DI decrease from birth to 1.5 months, then it rose without reaching the initial values. Like in the case with rats, DI had a close correlation with the erythrocyte parameter of shape (O min).     

Morphofunctional properties of red blood cells of humans in 5-day dry immersion

The blood of six healthy male volunteers sampled before, immediately after, and 7 days after 5-day dry immersion was analyzed for morphological parameters, erythrocyte metabolism, and lipid and phospho-lipid levels. The experimental 5-day exposure was shown to increase the erythrocyte count. On the first day after the experiment, upward trends were exhibited by hemoglobin and packed cell volume (PCV). The significant decrease in adenosine triphosphate and low level of reduced glutathione that were also detected on the first day after the experiment could be the result of enhanced oxidation in the cell, possibly due to the activation of lipid peroxidation. A downward trend in the phospholipid fraction of the erythrocyte membrane against constant levels of cholesterol and its ethers could be associated with a significant increase in the fraction of nonesterified fatty acids on day 1 and triglycerides on days 1 and 7 after the experiment.     

Age-related hematological changes in normal F344 rats: during the neonatal period.

In order to clarify age-related changes in hematological values of normal rats after birth, blood samples from neonatal F344 rats of both sexes were examined periodically during the period from 0 to 40 days postpartum. The erythrocyte count (RBC) increased with time after birth as a function of age. In contrast, the reticulocyte count (Retics) continuously decreased with time after birth. Hemoglobin (Hb), hematocrit (Ht), and the mean corpuscular hemoglobin concentration (MCHC) tended to decrease after birth until weaning (about 21 days postpartum), but they began to increase after weaning. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) also gradually decreased after birth until weaning, but they were unchanged thereafter. The platelet count (PLT) gradually increased after birth and reached a plateau at weaning. Microscopic examination of blood smears revealed that erythrocytes at birth had characteristic morphological features such as anisocytosis, polychromasia, basophilic stippling, Howell-Jolly body, and erythroblastosis. These characteristic features, however, disappeared by 30 days after birth. The total leukocyte count (WBC) gradually increased with time after birth, due to an increase in the number of lymphocytes. The lymphocyte count started to rapidly increase within several days after birth and the increase continued thereafter. Other differential leukocyte counts also showed various characteristic patterns of changes during the neonatal period. There were no apparent differences between males and females in these changes in hematological values.     

Appearance and accumulation of the brain specific S 100 protein in the developing nervous systems of rat, rabbit and guinea pig.

The appearance and accumulation of S 100 protein during postnatal development of rats and rabbit, and during pre- and postnatal development of guinea pig, was studied quantitatively by immunoelectrophoresis. High amounts of S 100 were found in newborn guinea pig brain. In rabbit and rat central nervous systems the content of S 100 rose linearily between the 1st and the 3rd and 4th weeks of postnatal life, respectively. From this later period to the adult animal there was a small increase in the amount of S 100 in rabbit and rat brain. The results of this study are compared with other studies on S 100 accumulation during postnatal development of rat, rabbit and guinea pig, using immunofluorescence and immunoelectron microscopic techniques.     

Radioimmunoassay of progesterone in peripheral and placental blood of pregnant rabbits and guinea pigs

Radioimmunoassay of progesterone in systemic and placental blood of pregnant rabbits and guinea pigs. 1. The level of progesterone in pregnant rabbits and guinea pigs serum was measured directly (without extraction) using a RadioImmunoAssay (RIA). 2. Hormonal concentrations in systemic blood were shown to increase with gestational age, being at their highest half-way through pregnancy (16.03 +/- 2.63 ng/ml for rabbits; 319.01 +/- 42.10 ng/ml for guinea pigs) and decreasing at the end of the pregnancy. 3. Progesterone was not detectable in rabbit placental blood, whereas a high level of this hormone was found in guinea pig placental blood, which increased with gestational age. From the 28th to the 56th post-coital day, the level increased from 143.22 +/- 13.15 to 283.30 +/- 36.84 ng/ml. 4. The method used enables to measure correctly progesterone concentrations in rabbit and guinea pig serum without extraction.     

三个品种豚鼠血液蛋白多态性的比较分析

目的比较分析白毛黑眼（WHBE）豚鼠和DHP豚鼠、花色豚鼠三个品种豚鼠在13个血液蛋白位点上的多态性。方法采用垂直板浓度和pH均不连续的聚丙烯酰胺凝胶电泳法对WHBE豚鼠、DHP豚鼠和花色豚鼠的66只个体的后白蛋白（Po）、前转铁蛋白1（Prt1）、前转铁蛋白2（Prt2）、转铁蛋白1（Tf1）、转铁蛋白2（Tf2）、后转铁蛋白（Ptf）、慢α球蛋白（Sag）、红细胞酯酶（Es）、血清酯酶1（Est1）、血清酯酶3（Est3）、血红蛋白α（Hbα）、血红蛋白β（Hbβ）和白蛋白（Alb）共13个蛋白位点进行了电泳及染色,再利用电泳图谱对各蛋白位点基因频率、平均杂合度和遗传距离进行计算,然后结合聚类分析。结果 Tf1、Tf2、Ptf、Est1和Es在三个豚鼠品种中表现为多态,其中Tf1可作为识别WHBE豚鼠的遗传标记。Po、Prt1、Prt2、Sag、Est3、Hbα、Hbβ和Alb等位点在三个豚鼠品种中的表型一致。Hardy-Weinberg平衡状态分析表明,Es为DHP豚鼠的高度不平衡位点。Ptf为花色豚鼠的高度不平衡位点。在WHBE豚鼠中,Tf1为高度不平衡位点,Est1为不平衡位点。在三个豚鼠品种中,所检测的13个蛋白位点的平均杂合度的排列顺序为：花色豚鼠（0.350 1）〉WHBE豚鼠（0.339 0）〉DHP豚鼠（0.313 5）。聚类分析结果表明,花色豚鼠和WHBE豚鼠的遗传遗传距离最近（0.064 3）,DHP豚鼠与花色豚鼠的遗传距离最远（0.179 2）。结论利用这些蛋白位点可以有效鉴别WHBE豚鼠、DHP豚鼠和花色豚鼠血液蛋白的遗传多态性。     

Purification of blood carbonic anhydrases and specific detection of carbonic anhydrase isoenzymes on polyacrylamide gels with 5-dimethylaminonaphthalene-1-sulfonamide (DNSA).

Methods are presented for purification of carbonic anhydrases from guinea pig blood and specific visualization of carbonic anhydrase bands during and after electrophoresis using nondenaturing polyacrylamide gels. The carbonic anhydrases are detected on the gels as fluorescent complexes with 5-dimethylaminonaphthalene-1-sulfonamide in protein mixtures and in erythrocyte lysates that have been prechromatographed to remove hemoglobin.     

Postnatal development of mitogen responsiveness of guinea pig lymphocytes.

Guinea pigs are believed to be immunologically mature at birth. There is, however, little data available to support this concept. In this study, the postnatal development of the lymphocyte responsiveness to Tand B-cell mitogens in the guinea pig was investigated. The results show that guinea pigs are not immunologically mature at birth as to the mitogenic responses of blood lymphocytes. The constant level of PHA response in the blood is achieved from the age of 1 to 2 months and that of Con A at the age of 3–6 months. Furthermore, the results support the concept that the emigration of thymocytes occurs also during postnatal life. The emigration of PHA-responsive thymic cells seems to precede and be greater than that of Con A-responsive cells. These findings provide important clues for studies on the ontogenetic development of cell-mediated immunity.     

The Effect of Erythrocyte Lysis in Selected Animals on the Absorption Spectra of Oxyhemoglobin

Biophysics - Abstract—The absorption spectra of lysed and non-lysed erythrocyte samples isolated from chicken, goose, and guinea pig blood were studied. It was found that the position of the...     

Cellular immune reactions and blood cerebrospinal fluid barrier dysfunction in guinea pigs

Both young and adult strain 13 guinea pigs have been treated with complete Freund's adjuvant (CFA). In young animals CFA induced an increase in the lymphocyte cell count in blood and a reversible blood CSF barrier impairment. Both these effects could be suppressed by the immunosuppressant drug Cyclosporin A. In contrast to the young animals treatment with CFA in adult strain 13 guinea pigs influenced neither the lymphocyte cell count nor blood CSF barrier function. In young and adult CFA-treated animals the number of polymorphonuclear cells in blood were increased and this increase was not reversed by Cyclosporin A. We discuss the influence of a systemic immune stimulation and suppression on blood CSF barrier function for proteins and its relevance to the pathogenesis of inflammatory diseases of the central nervous system.     

Morphogenesis and ductal development of the prostatic complex of the guinea pig

The morphogenesis of glandular architecture of the three lobes of prostate gland of the guinea pig, lateral, dorsal, and coagulating gland was studied from 35 days gestation to 90 postnatal days. Epithelial ductal tubules of various lobes of the gland were microdissected after treatment by collagenase and displayed two dimensionally. The number of ductal tips was counted, and the volume of the ductal network was quantified using a graphic tablet. The results show that the growth and ductal morphogenesis fall into two phases: prenatal and postnatal. The first outgrowth of prostatic buds begins at 35 days gestation (gestational length is 65 days). Ductal growth and branching continues over the next 15–20 days and by 55 days gestation, approximately 60%, 79%, and 71% of the adult number of ductal tips of the lateral and dorsal lobes and coagulating gland respectively, are formed. The figures increase to 89%, 84%, and 106%, respectively, by birth. There is little increase in number of ductal tips thereafter. Postnatal growth is accomplished mainly by elongation of existing ductal network with a little additional branching but with an increase in size (volume) of the tubules. Canalization of ductal tubules occurs prenatally in all lobes but postnatal functional cytodifferentiation takes a slightly different pace among them. Ductal morphogenesis of the guinea pig prostate gland differs significantly in time-course from that of the mouse in which ductal development occurs mainly postnatally. © 1993 Wiley-Liss, Inc.     

Postnatal development of the circadian rhythm of circulating blood cells in rats

In the present study the variations in the leukocyte and erythrocyte counts were investigated in the peripheral blood within the light and darkness periods during the postnatal development of rats. The animals were kept under an artificial illumination regime (12 hours light, 12 hours darkness), and examined at the ages of 7, 14, 21, 28, 35 and 45 days, and in maturity (56 days). Erythrocyte counts exhibited no light-dark rhythm. The circadian rhythm of leukocyte counts developed in male and female laboratory rats in the fourth week of age.     

Experimental infection with the Toxoplasma gondii ME-49 strain in the Brazilian BR-1 mini pig is a suitable animal model for human toxoplasmosis

Toxoplasma gondii causes toxoplasmosis, a worldwide disease. Experimentation with pigs is necessary for the development of new therapeutic approaches to human diseases. BR-1 mini pigs were intramuscularly infected with T. gondii with tachyzoites (RH strain) or orally infected with cysts (ME-49 strain). Haematology and serum biochemistry were analysed and buffy coat cells were inoculated in mice to determine tachyzoite circulation. No alterations were observed in erythrocyte and platelet values; however, band neutrophils increased seven days after infection with ME-49. Serology of the mice inoculated with pig blood leucocytes revealed circulating ME-49 or RH strain tachyzoites in the pigs'' peripheral blood at two and seven or nine days post-infection. The tachyzoites were also directly observed in blood smears from the infected pigs outside and inside leucocytes for longer periods. Alanine-aminotransferase was high at days 21 and 32 in the RH infected pigs. After 90 days, the pigs were euthanised and their tissue samples were processed and inoculated into mice. The mice serology revealed the presence of parasites in the hearts, ileums and mesenteric lymph nodes of the pigs. Additionally, cysts in the mice were only observed after pig heart tissue inoculation. The infected pigs presented similar human outcomes with relatively low pathogenicity and the BR-1 mini pig model infected with ME-49 is suitable to monitor experimental toxoplasmosis.     

Pig red blood cell hexokinase: Regulatory characteristics and possible physiological role

The regulatory properties of pig erythrocyte hexokinase III have been studied. Among mammalian erythrocyte hexokinases, the pig enzyme shows the highest affinity for glucose and a positive cooperative effect with n_H = 1.5 at all the MgATP concentrations studied (for 0.5 to 5 mm). Glucose at high concentrations is also an inhibitor of hexokinase III. Similarly, the apparent affinity constant for MgATP is independent of glucose concentration. Uncomplexed ATP and Mg are both competitive inhibitors with respect to MgATP. Glucose 6-phosphate, known as a stronger inhibitor of all mammalian erythrocyte hexokinases, is a poor inhibitor for the pig enzyme (K_i = 120 μm). Furthermore, this inhibition is not relieved by orthophosphate as with other mammalian red blood cell hexokinases. A variety of red blood cell-phosphorylated compounds were tested and found to be inhibitors of pig hexokinase III. Of these, glucose 1,6-diphosphate and 2,3-diphosphoglycerate displayed inhibition constants in the range of their intracellular concentrations. In an attempt to investigate the role of hexokinase type III in pig erythrocytes some metabolic properties of this cell have been studied. The adult pig erythrocyte is able to utilize 0.27 μmol of glucose/h/ml red blood cells (RBC) compared with values of 0.56–2.85 μmol/h/ml RBC for the other mammalian species. This reduced capacity to metabolize glucose results from a relatively poor ability of the cell membrane to transport glucose. In fact, all the glycolytic enzymes were present and a low intracellular glucose concentration was measured (0.5 mm against a plasma level of 5 mm). Furthermore, transport and utilization were concentration-dependent processes. Inosine, proposed as the major energy substrate of the pig erythrocyte, at physiological concentrations is not as efficient as glucose in maintaining reduced glutathione levels under oxidative stress. Furthermore, newborn pig erythrocytes (fully permeable to glucose) possess hexokinase type II as the predominant glucose-phosphorylating activity. This fact and the information derived from the study of the regulatory characteristics of hexokinase III and from metabolic studies on intact pig erythrocytes permit the hypothesis that the presence of this peculiar hexokinase isozyme (type III) enables the adult pig erythrocyte to metabolize low but appreciable amounts of glucose.     

Visual classification of erythrocytes in blood smears from normal subjects and patients

Erythrocytes on specially prepared and coloured blood smears can be classified not only by idcture analysis but also by phase contrast microscopy. Parameters of change for the peripheral zone area and pallor area (phase contrast value PW and index of erythrocyte changes Ev-I) serve as classificators of visual technique. 449 blood smears of the same number of male and female grown-up persons, whose diagnosis was unknown at the time of evaluation, were used for evaluation. In 145 cases these were healthy test persons in clinical and laboratory respect (group I). 163 test persons were ill, but without any malignous neoplasias (group II), and in 141 patients an ensured malignous neoplasia could be found (group III). From those 308 test persons or patients respectively in group I + II 11 blood smears were falsely classified as positive (= 3.6%). In 5 from 141 cases in group III blood smears were falsely evaluated as negative (= 3.6%). The findings were statistically ensured by the t-test. Clinical parameters of evaluation gained with visual techniques of classification are in accordance with those gained with automatic picture analysis. The reasons for the good separating ability of PW and Ev-I are discussed. Visual techniques of classification are suitable for institutions of all grades of equipment.     

Dynamics of hematological blood parameters of white rats in postnatal ontogenesis

In experiments on Wistar rats, dynamics of blood hematologic and rheological parameters was studied from birth to the 3-month age. Results of this study indicate an intensive activity of the red bone marrow anlagen for the first 3 weeks of postnatal ontogenesis. This is manifested as an increase of the number of cells in the erythron system, a change of the erythrocyte acidic resistance, and a shift in the leukocytic formula. The boundary between the 2nd and 3rd weeks of ontogenesis is a critical period: there occur a sharp deceleration of erythropoiesis and a change of the age-related erythrocyte composition and of the blood leukocyte ratio towards the parameters characteristic of adult rats. The rise in the number of leukocytes and erythrocytes does not stop after this period. Until the 4-week age, the deformability index increases to be accompanied by an increase of hemoglobin hydration and improvement of the erythrocyte toroid shape. Subsequently, inversion of these processes occurs.     

Rat, Mouse, and Guinea Pig Brain Development and Microtubule Assembly

The development of in vitro microtubule assembly and of tubulin concentration have been studied during brain maturation in the mouse and the rat, two species which have postnatal brain development, and in one species which is mature at birth, the guinea pig. (a) The rate of tubulin assembly is very slow soon after birth in both the mouse and rat; it increases progressively with age until adulthood. In contrast, in the guinea pig this rate is maximal at birth and slower rates are seen only at foetal stages. (b) Postnatal changes in the lag period of assembly and in the minimal concentration of tubulin (Cc) required to obtain in vitro assembly are seen in the mouse and the rat; in contrast these parameters are constant at all postnatal stages in the guinea pig with longer lag periods and lower Cc values being seen only at foetal stages. (c) Maximal rates of assembly, minimal lag periods, and minimal Cc values are restored after addition of microtubule-associated proteins to foetal guinea pig or young mouse and rat preparations, suggesting that the difference in the kinetic parameters of assembly between these species depends on differences in the concentration or activity of these proteins. (d) Maximal tubulin concentrations are observed before birth in the guinea pig and approximately at day 10 in the rat and mouse. Lennon A. M. et al. Rat, mouse, and guinea pig brain development and microtubule assembly. J. Neurochem. 35, 804–813 (1980).