Showing papers on "Primate published in 1978"

The neurological organization of pathways between the dorsal lateral geniculate nucleus and visual cortex in old world and new world primates

Abstract: Pathways between the dorsal lateral geniculate nucleus (dLGN) and visual cortex in Old World (Macaca, Papio, Erythrocebus, Cercopithecus) and New World (Saimiri, Cebus) primates were studied after injections of horseradish peroxidase and H3 or S35 amino acids into the dLGN or visual cortex. Trans-synaptic autoradiography was also used to study these pathways after an injection of H3 proline-fucose into one eye. The subsequent autoradiographs of visual cortex showed that Old World primates have separate eye inputs (ocular dominance columns) in striate cortex, whereas New World monkeys have overlapping or non-separated eye inputs. In both primate groups the geniculocortical input to layer IVA formed a pattern which resembled a honeycomb in tangential sections, unlike the solidly labeled layer IVC. Also common to the two primate groups was a projection from dLGN to layer VI. There was no dLGN projection to any prestriate area in any of the primates. However, after an injection limited to the prestriate cortex of Macaca, light autoradiographic labeling was seen in the interlaminar zones and the magnocellular and S laminae, demonstrating a prestriate-dLGN pathway. Our results indicate that the primate visual system differs significantly from the cat in having no dLGN projection to area 18. There are also significant differences between primates in the level at which the possibility of binocularity (of an excitatory nature) first occurs in the striate cortex because in the species studied thus far with neuroanatomical methods, Old World primates have ocular dominance columns in layer IV but most New World monkeys lack them.

Type D primate retroviruses: a review.

Abstract: The prototype virus of the type D retroviruses is the Mason-Pfizer monkey virus (MPMV). MPMV was originally isolated from a breast carcinoma of a female rhesus monkey (an Old World monkey). MPMV is of obvious importance in that it is the only retrovirus thus far isolated from a mammary tumor of a primate and has been shown to have transforming potential for primate cells in vitro . Subsequent to the isolation of MPMV, viruses morphologically and immunologically indistinguishable from MPMV have been isolated from normal placenta and lactating mammary glands of other rhesus monkeys in captivity. Recently, viruses morphologically resembling MPMV have been isolated from a langur monkey (another Old World monkey) and from squirrel monkeys (a New World monkey). Based on nucleic acid hybridization studies, the latter 2 viruses represent endogenous viruses in their species of origin, whereas MPMV appears to be a horizontally transmitted virus containing gene sequences partially related to the langur monkey isolate. Studies on the immunological relatedness of the type D retroviruses have demonstrated interspecies cross-reactivities between the major internal and external proteins of the viruses. Furthermore, these viruses also share cross-reactivity of their major external glycoproteins with those of the type C baboon endogenous virus. These interspecies reactivities can also be demonstrated in natural sera from both imported and laboratory-bred monkeys. The demonstration of these interspecies cross-reactivities shared by distantly related primate retroviruses provides a means for detecting determinants that are representative of all primate retroviruses presently known and yet to be isolated and may provide new assays for detection of a human retrovirus.

Short-term memory in the rhesus monkey: effects of dopamine blockade via acute haloperidol administration.

Abstract: The effects of dopaminergic blockade on recent or short-term memory (STM) were evaluated in test-sophisticated rhesus monkeys. Each monkey was tested under several doses of the antidopaminergic haloperidol (0.006 to 0.05 mg/kg), in an automated, delayed-response procedure. The same procedure and test apparatus had previously been used to demonstrate profound STM impairments in aged rhesus monkeys and strikingly similar deficits in young monkeys given the anticholinergic scopolamine. The results of this study do not support the notion that dopaminergic mechanisms play a critical role in primate STM. Although significant impairments in delayed-response accuracy were observed with the higher doses of haloperidol, this impairment was unrelated to the duration of the retention interval, implying a more general, non-mnemonic dysfunction. Since the qualitative nature of this deficit is dissimilar to, and not as specific as that previously found in aged rhesus monkeys (or young monkeys given scopolamine), it is suggested that age-related changes observed in the dopaminergic system are less likely to be responsible for the aged STM impairments than comparable age-related changes in the cholinergic system.

Localization of Primate Calls by Old World Monkeys

Abstract: Monkeys (Macaca) were trained by operant conditioning techniques to report the minimum detectable change in location of a sound in space, and were tested with a series of recorded coo or clear call vocalizations. Acuity of localization varied from approximately 4 degrees to 15 degrees and was a function of the magnitude of the change in pitch (frequency modulation) of the different clear calls.

Molecular diversity among five different endogenous primate retroviruses.

Abstract: Genetically transmitted retroviruses of Old and New World monkeys include type C viruses isolated from baboons (M7), macaque (MAC-1), and owl monkeys (OMC-1) and type D viruses from langurs (PO-1-Lu) and squirrel monkeys (SMRV, M534). Each of these isolates is unrelated to the others by nucleic acid hybridization criteria and contains a unique array of virion-associated proteins which can be resolved by agarose gel filtration and polyacrylamide gel electrophoresis under denaturing conditions. The major structural protein of each virus has a distinct primary structure, as determined by two-dimensional tryptic peptide analysis, and is antigenically different from the others. The major virion phosphoproteins of endogenous primate type C viruses (pp15) are also different from those of type D viruses (pp13-pp14). Immunological and structural analyses show that the endogenous langur virus and the horizontally transmitted Mason-Pfizer virus of rhesus monkeys are closely related to one another, consistent with the sequence homology detected in their RNA genomes. Although certain radioimmunoassays detect interspecies antigenic determinants common to either the p30 or gp70 proteins of some of these viruses, no one assay has yet been designed which can detect all groups of endogenous primate retroviridae. The data lead to the conclusion that primates contain a minimum of three different sets of genetically transmitted type C and type D retroviral genes.

Immunological Relationships of Human and Subhuman Primate Pregnancy-Associated Plasma Proteins

Abstract: (1) Four pregnancy-associated plasma proteins cross-reactive with antibodies to the human pregnancy proteins were detected in several species of pregnant subhuman primates. In the case of the two apes studied (chimpanzee and orangutan), these appeared to be immunologically identical to the human PAPPs (PAPP-A, -B, -C, and HCS). In the old world monkeys analyzed, equivalent partially cross-reactive PAPPs were found; while in the new world squirrel monkey, only faint traces of cross-reactive PAPP-C and HCS were observed with the most sensitive methods used. (2) As in the human, these proteins appeared to be specific for pregnancy, not being detectable in nonpregnant animals, female or male. (3) The pregnant chimpanzee possessed significantly higher concentrations of PAPP-A and PAPP-C than did women at an equivalent stage of pregnancy, while the HCS and PAPP-B levels appeared to be approximately the same. (4) The primate PAPP-C analogues were more complex than human PAPP-C, often revealing multiple gel diffusion patterns with subfractions of differing electrophoretic mobilities. (5) Based on the changes of electrophoretic mobility upon exposure to neuraminidase, the subhuman primate as well as human PAPP-A and PAPP-C appeared to be glycoproteins containing sialic acid. (6) In the chimpanzee and rhesus monkey, as in the human, the levels of PAPP-A, PAPP-C, and HCS were appreciably higher during the third trimester of pregnancy than they were during the second trimester.

Influence of Ovarian Hormones on Prolactin Release in the Rhesus Monkey

Abstract: Blood samples were collected from female rhesus monkeys by two different techniques and serum prolactin levels were determined by radioimmunoassay. Prolactin levels in samples from ketamine anesthetized monkeys varied widely and there was no apparent difference between those of intact (23.5 ±4.2 ng/ ml. mean ± SEM) and ovariectomized (24.0±5.1 ng/ ml) monkeys. In contrast, when blood samples were taken from unanesthetized monkeys in primate restraint chairs. prolactin levels were 8.2±1.7 ng!ml in intact monkeys and were reduced to 2.5 ±0.4 ng/ml in ovariectomized monkeys. In ovariectomized monkeys, the peak release of prolactin following injection of either thyrotropin releasing hormone (TRU. 24 ug. iv.) or pimozide (0.2 mg/kg iv.) were reduced by 72% and 68%. respectively. Replacement of estradiol-l7�. by means of Silastic capsule implants for periods of 1-6 months, restored the responsiveness of ovariectomized monkeys to TRH. Pituitary weights in 7 ovariectomized monkeys treated with estrogen for 2-5 months were 81.0±3.1 mg as compared to 61.1±2.3 mg for 5 ovariectomized controls (P

Natural Distribution of Squirrel Monkey Retrovirus Proviral Sequences in Primate DNAs

Abstract: Summary 3H-labelled 70S RNA of squirrel monkey retrovirus (SMRV) hybridized to a high degree (> 52%) to the DNA of various tissues of two squirrel monkeys. Hybridization of the same probe to DNAs of other primates including New World monkeys (Woolly monkey, capuchin, owl monkey), Old World monkeys (rhesus, African green), apes (gibbon, chimpanzee), and human (A204 cells infected with MPMV) revealed no significant hybridization. Analysis of the kinetics of hybridization indicated that SMRV provirus was present in multiple copies in various squirrel monkey tissues (C 0 t ½ = 120 to 400) and in SMRV-infected A204 cells at a low number of copies (C 0 t ½ = 1500). These results demonstrate that SMRV is an endogenous virus of squirrel monkeys and the first isolated from a New World monkey.

The chemical restraint of apes and monkeys by means of phencyclidine or ketamine

Abstract: The anesthetic effects of two drugs, namely, Phencyclidine and Ketamine, used alone or in combination with atropine, were compared during clinical and experimental procedures on different primate species ranging from gorillas, orangutans, white-faced and dwarf chimpanzees, baboons, cercopithecus monkeys to new--world monkeys. It is concluded that both these anesthetics are very good and safe drugs for restraint and anesthesia. Ketamine appeared to be superior to Phencyclidine for use among apes and monkeys in so far as it is shorter acting, has wider safety margin and shorter recovery time, provides better muscle relaxation and is practically without side effects. But Phencyclidine has definite advantage in so far as it is needed is smaller quantity to produce comparable effect of anesthesia.

Subdivisions and Interconnections of the Primate Visual System

Abstract: For the last ten years or so, my colleagues and I have been trying to determine the subdivisions of the visual system and the interconnections of these subdivisions in primates. Since most of our research has been on a New World monkey, the owl monkey, Aotus trivirgatus this review is devoted to findings for this monkey. A more inclusive review will appear elsewhere (1).