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PubMed1991

Penile spines affect copulatory behaviour in a primate (Callithrix jacchus).

Androgen-dependent, keratinized "spines" occur on the glans penis in many rodents, primates and other mammals. Since penile spines overlie dermal tactile receptors, they may play a role in copulatory behaviour. An experiment was conducted to test this hypothesis. Sixteen sexually experienced adult male marmosets were paired with ovariectomized females before, and after, removal of penile spines (using thioglycollate cream applied to the glans under anaesthesia) or a sham operation. Spine removal resulted in an increased duration of preintromission pelvic thrusting (mean +/- s.e.m. from 6.87 +/- 1.09 to 14.94 +/- 3.32 s, p = 0.05) and of intromitted thrusting (from 1.73 +/- 0.11 to 2.0 +/- 0.11 s, p less than 0.05). Three males exhibited partial intromissions during some postspinectomy tests, an effect which had not been observed prior to the operation. Sham operations had no behavioural effects. Results indicate that penile spines play a significant (but not indispensible) role in sensory feedback during copulation in this primate species.

Androgens↗
PubMed1992

The relationship between cone pigments and behavioural sensitivity in a New World monkey (Callithrix jacchus jacchus).

Microspectrophotometric measurements of visual pigments and behavioural measurements of spectral sensitivity are reported for individual marmosets from 3 family groups. The sex differences and polymorphism that characterise the long-wave cone pigments in this species are well reflected by variations in the behavioural sensitivities. With one exception, the pattern of inheritance is compatible with a genetic model in which the long-wave pigment is specified by a single polymorphic locus on the X-chromosome. Measurements are also reported for the spectral absorbance of the marmoset lens, and these are used to reconstruct short-wave behavioural sensitivity from the microspectrophotometric measurements of the short-wave cones.

Animals↗
PubMed1989

Termination of pregnancy in common marmosets (Callithrix jacchus) following administration of antiserum to chicken riboflavin carrier protein.

The presence of protein(s) which is immunologically and functionally similar to the well characterised avian riboflavin carrier protein has been demonstrated in female common marmosets during pregnancy. The protein(s) that interacts with [14C]riboflavin has an immunological homology to chicken riboflavin carrier protein. The termination of pregnancy in four out of six marmosets following administration of antiserum to chicken riboflavin carrier protein supports the hypothesis that vitamin carrier protein ensures an uninterrupted supply of the vitamin to the growing embryo and that immunoneutralization of maternal riboflavin carrier protein leads to fetal death and termination of pregnancy.

Animals↗
PubMed1989

The distribution of glial fibrillary acidic protein and vimentin in postnatal marmoset (Callithrix jacchus) brain.

Antisera to glial fibrillary acidic protein (GFAP) and vimentin were used to elucidate the distribution of these intermediate filament proteins in postnatal marmoset brains of various ages. The ependyma of the lateral ventricles was unique in being equally immunoreactive for both GFAP and vimentin at all ages. Vimentin alone was consistently demonstrated in endothelial and leptomeningeal cells at all ages. In neonates, vimentin immunoreactivity greatly exceeded that of GFAP and was located primarily in radial glia in the subependymal plate of the anterior cerebrum. Their vimentin-positive processes formed thick fascicles in the corpus callosum but separated into fine fibres on entering the cortex. GFAP immunoreactivity in these cells and processes was very limited. With age, GFAP-positive cells increased in number and displayed the typical stellate appearance of astroglia. The vimentin-positive radial glial population decreased considerably during this period and by 6 months had virtually disappeared. The GFAP reaction in adult brain was even more widespread, largely due to the increased number of positive astrocytes in the white matter. Vimentin immunoreactivity in the adult was greatly diminished and positive radial glia were not detectable. A major change in intermediate filament protein expression, therefore, occurs in the early postnatal period and probably reflects phases in the differentiation of radial glial precursors into astrocytes.

Animals↗
PubMed1990

Cell proliferation in the subependymal layer of the postnatal marmoset, Callithrix jacchus.

Cells of the subependymal layer (SEL) have been shown to be capable of continued postnatal cell division throughout life in rodents. To determine if the primate brain behaves similarly, proliferative activity in the SEL of the marmoset has been investigated by tritiated thymidine autoradiography and bromodeoxyuridine immunocytochemistry. Both methods revealed the presence of DNA-synthesizing cells at all postnatal ages studied. The labelling index (LI), low at birth, reached a peak of almost 4% at one month but decreased gradually thereafter. In animals older than two years the LI was extremely low and labelled cells were rarely seen anywhere in the brain. The cell density of the SEL, in contrast to the low LI, was highest in neonates and decreased linearly with increasing age. Bromodeoxyuridine immunoreactivity revealed the distribution of proliferating cells in the SEL and neighbouring regions. Such cells were most abundant around the anterior lateral ventricle where the SEL was most evident. Proliferating cells were numerous in neonates, though not adjacent to the ependyma where counts for the LI were made, and were mainly located dorsally and ventrally at the junctions of the corpus callosum and caudate nucleus.

Aging↗
PubMed1986

Effects of variable linoleate intake on aortic PGI2-like activity and fatty acid composition: difference between rat and marmoset (Callithrix jacchus).

Two animal species, the laboratory rat and a non-human primate (the common marmoset) were compared with respect to the influence of dietary lipid supplementation on both fatty acid composition and prostanoid synthetic capacity of aorta. Standard chow (REF. diet) was supplemented (12% w/w) with either sheep fat (SF) or sunflower seed oil (SSO). Differences were apparent in the aortic phospholipid fatty acids from both animal models, as a result of the diet, although the type and the extent of changes displayed a considerable species variation. For example, after the SSO diet, the proportion of linoleic acid in rat aorta displayed only a modest increase whilst in marmosets it was doubled. No change was apparent in the proportion of arachidonic acid in rats, whereas the marmosets showed a reduction (P less than 0.05) with both lipid supplements. Rats fed the SF diet showed a considerable increase in aortic PGI2-like activity compared to REF. And SSO supplemented groups. In contrast, no dietary induced changes were observed in the aorta from marmosets despite compositional changes. The results indicate no direct association between the synthesis of PGI2-like activity and membrane lipids and demonstrate the need for careful selection of the proper animal model, particularly in nutritionally orientated experiments.

Animals↗
PubMed1989

Purification and properties of cytochrome P-450 from liver microsomes of phenobarbital-treated marmoset monkeys (Callithrix jacchus).

One form of cytochrome P-450 from phenobarbital-induced marmoset liver was purified to apparent electrophoretic homogeneity and compared with the major inducible form isolated from rat liver. Whereas spectral properties and molecular weights, as well as catalytic activities towards aminopyrine and ethylmorphine N-demethylation are quite similar, rates of O-dealkylation with enzymes from the two species are considerably different. While ethoxycoumarin deethylation for the marmoset cytochrome is about one-fortieth of that for the rat, ethoxyresorufin and even pentoxyresorufin dealkylations for the marmoset form are not detectable. By contrast, aldrin epoxidation as catalyzed by this cytochrome is about three times as high as that obtained from the rat.

Aldrin↗
PubMed1987

Controlled ovulation in the marmoset monkey (Callithrix jacchus) with human chorionic gonadotropin following prostaglandin-induced luteal regression.

Controlled induction of ovulation in the marmoset monkey was attempted with a single injection of human chorionic gonadotropin (hCG; 50 IU) given on day 7 after prostaglandin-induced luteal regression. Animals given hCG (n = 12) ovulated within a 2-day period (days 9 and 10 after prostaglandin) compared with a 4-day period (days 9 to 12) in the control group (n = 12). The mean interval to ovulation was similar in both groups. There was no difference in the timing of the preovulatory estradiol (E2) peak between groups, although E2 levels on the day of hCG injection were lower than in controls on the day of the onset of the luteinizing hormone surge. All animals given hCG ovulated and 11 of 12 became pregnant. Ten of 11 embryos recovered surgically from six of these animals were normal blastocysts; 5 of the remaining 6 animals carried pregnancies to term. The results are of practical importance for experiments involving follicular and oocyte maturation and the collection and transfer of embryos.

Animals↗
PubMed1988

Births following the transfer of cultured embryos obtained by in vitro and in vivo fertilization in the marmoset monkey (Callithrix jacchus).

The aim of this study was to determine whether marmoset monkeys are a suitable primate model for in vitro fertilization (IVF), embryo culture, and transplantation studies. A prostaglandin analogue given in early pregnancy and human chorionic gonadotropin given near the end of the ensuing follicular phase were used for controlling the reproductive cycle, timing oocyte collection, and synchronizing the cycles of oocyte donors and embryo recipients. Five embryos obtained by IVF were transferred at early stages to the uterus of three recipients, and two gave birth to live infants. Some of the embryos were cultured to advanced blastocyst stages. In vivo fertilized oocytes were also cultured and transferred to two recipients, and one gave birth. We concluded that the marmoset is one of the best primates for such investigations.

Animals↗
PubMed1995

Luteinizing hormone/chorionic gonadotropin bioactivity in the common marmoset (Callithrix jacchus) is due to a chorionic gonadotropin molecule with a structure intermediate between human chorionic gonadotropin and human luteinizing hormone.

Chorionic gonadotropin (CG), a pregnancy-specific heterodimeric hormone found in primates, is responsible for CL rescue with pregnancy maintenance. Of the primates, the human and baboon gene sequences are the only structures so far determined. In order to study the structure and function of CG in other primates, we have isolated and sequenced the coding regions for the two subunits of marmoset CG (mCG) by the reverse transcription/polymerase chain reaction method. Study of multiple clones confirmed a high degree of homology with the human sequences (88% and 80% for the alpha and beta nucleotide sequences, respectively). Marmoset CG alpha has an extra four amino acids compared to hCG alpha, whereas the mCG beta sequence has a 3-bp deletion that maintains the reading frame and C-terminal amino acid sequence. Most of the differences between hCG beta and mCG beta peptides occur in the C-terminal region, which includes the loss of two of the O-linked glycosylation consensus sequences and the presence of an N-linked glycosylation consensus sequence. When mCG alpha and beta were co-expressed in CHO cells, assembly of biologically active hormone was confirmed by induced steroid secretion by MA10 cells. Partially purified mCG beta was used to raise anti-mCG antibodies. To date, an antibody has been obtained that is capable of detecting recombinant mCG beta, recombinant mCG dimer, and mCG dimer secreted by cultured marmoset trophoblast. Marmoset CG alpha and beta were also detectable at the transcriptional level in cultured trophoblast by in situ hybridization. This suggests that the LH/CG bioactivity reported from marmoset placentae and embryos is due to a molecule with structural features common to hLH (glycosylation pattern) and hCG (CG beta C-terminal structure).

Amino Acid Sequence↗
PubMed1991

Immunohistochemical localization of collagenous components in healthy periodontal tissues of the rat and marmoset (Callithrix jacchus). II. Distribution of collagen types IV, V and VI.

The immunohistochemical distribution of collagen types IV, V and VI has been demonstrated in healthy periodontal tissues of rats and marmosets following decalcification of the maxillae and mandibulae in 0.2 N HCl. An intense fluorescence with anti-collagen type IV antibodies was demonstrated in the basement membranes of the epithelium and of the blood vessels and nerves. In the alveolar bone stroma and in the periodontal ligament (PL) collagen type IV was present only in the basal membranes of the blood vessels and nerves. In comparison, collagen type V was observed in a fibrillar pattern in the gingival connective tissue, as well as the PL. In the PL, type V collagenous fibers demonstrated a parallel distribution with stronger fluorescence near the cementum surface. Collagen type VI could be demonstrated in fine fibers present in the gingival connective tissue and the PL. Blood vessels and nerves were not stained in the marmoset, but were in the rat, where a localization of collagen type VI was demonstrated in these areas. Alveolar bone and cementum, as well as the Sharpey's fibers embedded in these tissues, were not stained with antibodies against collagen type V and type VI, but a pericellular localization of these collagenous components could be observed. Collectively, these results provide basic information on the relative distribution of different collagen types in normal tissues of rats and marmosets that will be required for future studies on the effects of pathological, reparative and regenerative processes.

Animals↗
PubMed1992

Immunohistochemical localization of collagenous components in healthy periodontal tissues of the rat and marmoset (Callithrix jacchus). I. Distribution of collagen types I and III.

The distribution of collagen types I and III was demonstrated in healthy periodontal tissues of the rat and marmoset using immunofluorescent localization after decalcification of the maxillae and mandiblae in 0.2 N HCl. An intense fluorescence in the alveolar bone and cementum matrix, as well as in the soft periodontal tissue, was demonstrated with anti-collagen type I antibodies. In the gingival connective tissue and in the periodontal ligament thick fibers of collagen type I could be observed. The fluorescent reaction in the rat periodontal ligament was not strong in comparison to the marmoset periodontal ligament. Sharpey's fibers, inserting into the cementum and alveolar bone, were also stained. On the other hand, collagen type III could not be demonstrated in the hard periodontal tissues, but could be in the bone marrow stroma and the incremental lines as well as around the Sharpey's fibers of the cementum, in accordance to previous studies. In the gingival connective tissue a strong staining was evident, especially near the basement membrane. The periodontal ligament showed an intense fluorescence that was, in some areas, continuous with Sharpey's fibers inserting into the cementum. The distribution of collagen types I and III was demonstrated with immunohistochemical techniques in the rat and marmoset periodontium. These results provide necessary information on healthy tissues that will be required for future studies on the effects of pathological, reparative and regenerative processes.

Alveolar Process↗