Early placentation in the African green monkey (Cercopithecus aethiops)

Placentation in the green monkey (Cercopithecus aethiops) from gestational ages of 18-30 days was studied by light and electron microscopy. The placentae show many features in common with that of the rhesus monkey and other related macaques. Implantation is superficial and bidiscoid, and the placenta is classified as villous and hemomonochorial. Epithelial plaque formation and a moderate stromal reaction occur. Plaque cells are large, with massive deposits of glycogen and marginal pleomorphic dense bodies. Observations further support the concept that chorionic blood vessels, angioblastic and mesenchymal cells are not derived by delamination from cytotrophoblast. Capillary formation is by attachment of one or more mesenchymal cells and/or their processes. Embryonic blood was not observed in the villi until after day 22.     

T-cell lymphosarcoma in a female African green monkey (Cercopithecus aethiops)

A female African green monkey developed a generalized lymphosarcoma spontaneously that clinically and pathologically resembled malignant lymphoma in human beings infected with human T-lymphotropic virus type I. The monkey was serologically positive for simian T-lymphotropic virus. Immunocytochemical analysis of routinely fixed and paraffin embedded tumor tissue demonstrated neoplastic cells that stained positive with antihuman monoclonal UCHL1 which recognized a T-cell-restricted isotype of leukocyte common antigen.     

Variable satellite DNA's in the African green monkey Cercopithecus aethiops

A heavy component of Cercopithecus aethiops DNA has been observed which comprises a small but variable portion of the monkey genome. This variability exists both within and among different monkey cell lines. In general, cell lines with larger amounts of this heavy component showed virus-induced host DNA synthesis on lytic infection with SV-40 virus. The heavy component, which has a buoyant density of about 1.711 g/ml in CsCl, consists of at least two minor satellite DNA's, designated components and . By in situ hybridization, component was localized to the pericentromeric heterochromatin of monkey chromosomes in all cell lines examined. In contrast, component sequences were scattered over the monkey karyotype. Component reassociated with more precision than component . However, neither component nor component reassociated as rapidly and completely as component , the major monkey satellite DNA which comprises 20–25 percent of the monkey genome.     

Reproductive and hormonal patterns in the African green monkey (Cercopithecus aethiops).

The results of breeding Cercopithecus aethiops under time-mated laboratory conditions and analysis of total estrogen, progesterone, and LH concentrations in plasma during the menstrual cycle and plasma estrogen and progesterone concentrations during pregnancy indicate that this species is a suitable alternative for the rhesus monkey as a model for investigations of reproductive function in man.     

Characterization of a spontaneous undifferentiated carcinoma from an African green monkey (Cercopithecus aethiops).

An adult male African green monkey (Cercopithecus aethiops) with an undifferentiated carcinoma, probably originating from the nasal mucosa, was received from the Akron, Ohio zoo. Cultivation of this tumor in vitro resulted in a mixture of fibroblastic and epithelial cells which was subsequently separated using differential trypsinization. The neoplastic nature of the cultured epithelial cells was verified by their ability to transplant into athymic nude, or antithymocyte serum-treated mice, where poorly differentiated carcinomas were produced, and cultures of the tumors that arose in nude mice were morphologically similar to pretransplantation cultures. Early cultures showed a normal male karyotype characteristic of the species; however, in long-term cultures, a clearly defined, small submetacentric Y chromosome was not observed. Electron microscopic examination of tumor tissue and cultured tumor cells revealed desmosomes and the presence of cytoplasmic (keratin-type) fibrils, which tended to be organized around the nucleus. In addition to the keratin-type fibrils, the cultured tumor cells also contained a large amount of cytoplasmic inclusion material that may represent keratohyalin granules. There was no evidence of a viral association with tumor material or cultured cells. The cultures were susceptible to infection by vesicular stomatitis virus, Herpesvirus hominis type 1, and H. saimiri, but were resistant to the Epstein-Barr virus.     

Pulmonary immunoreactive calcitonin in the African green monkey (Cercopithecus aethiops): Anatomic distribution

The hormone calcitonin, which occurs predominantly within the C cells of the mammalian thyroid gland, is also found within the pulmonary endocrine cells of the epithelium of the tracheobronchial tree. A study was made of the distribution of immunoreactive calcitonin (iCT) in the African green monkey. Using two different region-specific antisera, the total respiratory iCT comprised 2.5% and 5.8% of the total thyroid iCT. The mean concentration of iCT in the right lung exceeded that in the left, and the mean concentration of the right middle or right upper lobe exceeded that of all other lobes. Embryologically, the ultimobranchial bodies contribute their iCT-producing C cell primordia to the thyroid gland near the level of the primitive laryngotracheal cleft and shortly after the early arborization of the bronchial tree. In monkeys and most other mammals, the right main stem bronchus is larger and develops earlier than the left. The data suggest an early migration of cells from the ultimobranchial bodies to the bronchi, eventually giving rise to the iCT-containing pulmonary endocrine cells.     

Molecular cloning and initial characterization of African green monkey (Cercopithecus aethiops) corticotropin releasing factor receptor type 1 (CRF1) from COS-7 cells

We report the expression of endogenous CRF1 in COS-7 cells (African green monkey origin). Cloning of the coding region of CRF1 gene identified three alternatively spliced isoforms with nucleotide and predicted amino acid sequences corresponding to the membrane bound alpha and c and soluble e isoforms. DNA sequencing of the main isoform CRF1alpha showed homologies of 99%, 97% and 91% with the rhesus monkey, human and rodent genes, respectively; the deduced protein sequence differed in only one amino acid with rhesus monkey and human. Western blot analysis with antibodies against human CRF1 demonstrated immunoreactive proteins with MW of 37, 52, 70 and 80-85 in crude membrane or cytoplasm preparation; two additional species of 40 and 60 kDa were detected only in the cytoplasmic fraction. On immunocytochemistry CRF1 was localized to both the cell surface and intracellularly. The receptor was functional, e.g., addition of CRF to COS-7 cells inhibited cell proliferation and stimulated release of arachidonic acid; nevertheless, it was poorly coupled to cAMP production (its stimulation was minimal in native cells). In conclusion, COS cells that are routinely used for the study of transfected CRF receptors do express endogenous CRF1 mRNA with splicing behavior similar to that reported in human and rodent cells, and translated into functional CRF1 receptors.     

Age-related changes of immunoglobulin levels in African green monkeys (Cercopithecus aethiops)

Serum IgG, IgA, and IgM levels were measured in domestically bred African green monkeys (Cercopithecus aethiops) ranging in age from 0 day to 49 months as well as in adult (5 years or older) animals of wild origin. Transplacental transfer of IgG was observed. IgG, IgA, and IgM levels increased with increasing age except for a temporal decrease of IgG level in the first month of life.     

Circadian rhythm of cholesterol-7alpha-hydroxylase and cortisol in the African green monkey (Cercopithecus aethiops).

Cholesterol-7alpha-hydroxylase in African green monkey liver had an apparent Km of 1.65-10(-4) M cholesterol and a pH optimum of 7.4. The amplitudes of the circadian maxima of enzyme activity and serum cortisol levels were significantly greater in vervets than in grivets. Fluctuations in enzyme activity and cortisol levels during the circadian cycle were positively correlated (r = 0.89). Enzyme activities and hormone levels were 2.7-fold lower over a 24-h period in the grivet than in the vervet. Cholesterol feeding reduced the enzyme activity by 40% and serum cortisol was reduced to 38% of control levels at the diurnal peak. Serum glucocorticoids may be important physiological regulators of cholesterol-7alpha-hydroxylase in non-human primates. The concentration of cortisol and its time of release appear to be factors in the hyperresponsive trait of grivets. Genetic differences between vervet and grivet races may account for differences in the amplitude and timing of the circadian rhythm of cholesterol-7alpha-hydroxylase activity possibly influenced by cortisol.     

Noninvasive measurement of blood pressure in African green monkeys (Cercopithecus aethiops)

Indirect measurements of arterial blood pressure were made in African green monkeys (Cercopithecus aethiops) employing a Doppler ultrasound stethoscope and standard cuff and an Infrasonde automatic blood pressure recorder. Measurements were obtained from anesthetized (10 mg/kg ketamine (HCI) and unanesthetized (1.5 mg/kg ketamine HCI) animals. Ketamine had no significant effect on blood pressure. Indirect measurements from the brachial artery were compared with direct femoral artery measurements and with each other. Systolic blood pressures measured by the Doppler (r = .948) and Infrasonde (r = .920) methods correlated closely with direct measurements but were significantly lower than systolic blood pressures measured by the direct method. Diastolic blood pressures measured by the Infrasonde method agreed closely with direct measurements (r = .947). Systolic blood pressures measured by the indirect methods correlated closely in both anesthetized (r = .973) and unanesthetized (r = .834) animals and were not significantly different. Mean blood pressures calculated from direct and Infrasonde measurements also correlated closely (r = .963), with direct measurements being 4 mmHg higher on the average. Mean blood pressures are less influenced by methodology and are more reproducible than other pressures. These noninvasive methods can be used to obtain simple and accurate measurements of blood pressure from anesthetized and unanesthetized monkeys and are of value in long-term studies in monkeys.     

Breeding of African green monkeys (Cercopithecus aethiops) under indoor individually-caged conditions.

This paper reports the results of reproduction with 45 wild African green monkeys (Cercopithecus aethiops) (36 females and 9 males) during the nine years from 1981 to 1989 under indoor individually-caged conditions. In 206 cases of menstruation observed, menstrual discharge lasted for 2.5 +/- 1.2 days in cycles of 22-48 days, and the length of each menstrual cycle was 31.2 +/- 6.5 days. Females who had regular menstrual cycles were subjected to "one-to-one timed mating"; females and males were put together on a one-to-one basis daily only for a certain period of time on and after the day of ovulation. Females who had irregular menstrual cycles or had no menstruation were subjected to "every-other-day mating"; females and males were put together on a one-to-one basis every other day for at least 16 weeks. The pregnancy rate (No. of pregnant females/No. of mated females) by one-to-one timed mating was 48.9% (116/237); 2.0 mating trials were needed to obtain one case of pregnancy. On the other hand, the pregnancy rate (No. of pregnant females/No. of mating trials) by every-other-day mating was 96% (48/50). Females who delivered normally totaled 129. The mean gestation period was 165 days when males, weighing 343 g on average at birth, were delivered, and 166 days when females, weighing 318 g on average at birth, were delivered. The male and female newborns were nursed for 131 and 138 days, respectively, on average. Details are summarized in Table 3. This paper also reports 23 cases of abortion, 6 stillbirths, and 6 cases of Caesarean section, by which three live fetuses and three dead fetuses were obtained.     

In vitro fertilization and preimplantation embryo development of African green monkeys (Cercopithecus aethiops)

Ovaries of five adult female African green monkeys were stimulated by repeated administrations of equine chorionic gonadotrophin (eCG), followed by a single administration of human chorionic gonadotrophin (hCG). Oocytes were collected from enlarged follicles 28 h after hCG administration and incubated in vitro for 288 h. Oocytes that had extruded the first polar body were inseminated with spermatozoa that had been incubated for 4 to 6 h in medium with caffeine and dibutyryl cyclic AMP. Of these oocytes, 66% were fertilized and the incidence of polyspermy was 37%. Eighty-two percent of the fertilized eggs cleaved, with some developing into expanded blastocysts. Am. J. Primatol. 43:43–50, 1997. © 1997 Wiley-Liss, Inc.     

Developmental staging and thalidomide teratogenicity in the green monkey (Cercopithecus aethiops).

The developmental stages of 11 Cercopithecus aethiops embryos, 24 to 45 days post-mating, are described. The onset of organogenesis in this species is approximately five to seven days later than that reported for macaques and baboons. This temporal difference in the embryonic period is an important factor in the analysis of the subsequent teratogenic study. Oral administration of thalidomide in single or multiple (3-day) treatment periods to pregnant green monkeys between days 28 and 33 resulted in defects of the limbs which resemble those observed in macaques and baboons. However, the sensitive period occurs approximately four days later than that reported for another nonhuman primates. These results indicate that the sensitive period of the limbs to thalidomide coincides with their earliest development.