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D M Bowden

Publications and source records attributed to D M Bowden.

At least 19 recordsLinked to original sources
PubMed1991

A system to acquire and record physiological and behavioral data remotely from nonhuman primates.

We describe an integrated system to record physiological and behavioral variables from nonhuman primates in social groups. The system records data simultaneously from two animals in family groups of five. It synchronizes behavioral and physiological data within 16 ms, either on-line or from recordings. Behavioral data are entered by trained observers on-line or from videotape. Recordings of physiological data are produced on-line as stripchart records, tape recordings on the audio channels of video cassettes, and magnetic disk files. The physiological data include two arterial blood flows, arterial blood pressure and heart rate. The data are transmitted from freely behaving animals to a central site via radio telemetry. The infrared link controls the radio transmitter and physiological signal processing electronics, as well as two sources of drugs for each animal. All of the electronics are contained in a small, light backpack that can be worn by either male or female baboons.

Animals↗
PubMed1991

Integrating behavior and cardiovascular responses: the code.

The next revolution in biology is predicted to be in the integrative domain, and the need to involve physiologists in this kind of research has been recognized. This paper represents an approach to providing some of the tools required for dealing with integrative physiology at the behavioral level. Video tape recordings are made of the activities of a group of five baboons (Papio hamadryas) while simultaneous recordings of arterial blood pressure, heart rate, renal blood flow, and mesenteric or iliac blood flow are telemetered from two of the members of the group. The telemetered cardiovascular information is recorded on the two audio channels of the videotape. Subsequently the videotape is viewed, and a two-dimensional code is used to record the behavior of the two animals with the telemetry equipment. The first dimension of the code categorizes the behavior changes precisely regarding those aspects of behavior that are related to cardiovascular dynamics and does so with an accuracy of 16 ms. The second dimension codes relevant environmental changes. The paper describes the code and presents illustrations of how the code reflects the cardiovascular dynamics associated with the behavioral changes.

Animals↗
PubMed1990

Central nervous system effects of lactate infusion in primates.

The concentration of total lactate in cisternal fluid increased threefold, from 12.3 +/- 2.1 to 37.6 +/- 8.9 mg/dl, during a 20-min intravenous infusion of 1 M racemic sodium lactate (10 mEq/kg) in 3 anesthetized, mechanically ventilated baboons. Rises in cisternal lactate lagged behind arterial lactate increases, but occurred during the time interval in which susceptible humans typically panic in response to lactate infusion. Subsequent to cisternal lactate increases, cisternal pH and HCO3- concentration progressively increased during a 105-min interval following lactate infusion. No consistent changes in cisternal pCO2 occurred during or subsequent to lactate infusion. These preliminary findings fail to support the hypothesis that lactate-induced panic is mediated by increasing central nervous system pCO2. Instead, these data demonstrate that lactate can rapidly increase in the central nervous system during lactate infusion, suggesting new lines of investigation for studying the mechanisms responsible for lactate-induced panic.

Animals↗
PubMed1990

Fingernail growth rate as a biomarker of aging in the pigtailed macaque (Macaca nemestrina).

Rate of fingernail growth (FNG) of the middle digit of the right hand was assessed in 46 healthy pigtailed macaques at approximately 6-month intervals for 4 to 6 years. Mean FNG for 24 females, ranging in mean age at measurement from 7 to 24 years, was 104 mu/day; the mean for 22 males, ranging from 7 to 20 years, was 111 mu/day. Longitudinal analysis showed that FNG declined in animals of both sexes and that the rate of decline (-4.8 mu/day/year) did not differ between them, i.e., the mean regression coefficients (beta) of the two sexes were significantly different from zero and not significantly different from each other. Results of cross-sectional analysis differed from those of longitudinal analysis in that the mean FNG appeared to be more rapid in males than in females, particularly in the older animals. Inter- and intra-individual variability in FNG did not increase with age. FNG appears to be an excellent functional marker of the rate of aging because the direction of change is essentially decremental, a significant degree of change can be detected in a few years, and the rate of change is relatively constant across the adult lifespan. In addition, measurement of FNG is innocuous, quantitative, inexpensive, and simple.

Aging↗
PubMed1990

Constructing an instrument to measure the rate of aging in female pigtailed macaques (Macaca nemestrina).

To develop a battery of innocuous tests measuring individual differences in the rate of biological aging, longitudinal data were gathered on 28 biochemical, physiological, and morphological characteristics of 40 adult female pigtailed macaques. The change in each variable over time, i.e., the beta coefficient of linear regression, was calculated for each animal, and a matrix of correlations among the variables was constructed. Eight variables correlated well with the first principal component of the matrix. These variables (rate of fingernail growth, blood lymphocytes, mean corpuscular hemoglobin, immunoglobulin A, and serum sodium, chloride, total protein, and creatinine) represented the best subset of the potential biomarkers analyzed to produce an index covering a range of morphologic and functional systems that change with age. A similar set representing a wider range of systems and measured over a larger fraction of the life span should provide a valid index of an individual's rate of biological aging.

Aging↗
PubMed1990

Neuroanatomic and neurochemical abnormalities in nonhuman primate infants exposed to weekly doses of ethanol during gestation.

Ethanol was orally administered once per week to 54 gravid pigtailed macaques (Macaca nemestrina) in doses of 0.0, 0.3, 0.6, 1.2, 1.8, 2.5 or 4.1 gm/kg from the 1st week in gestation or in doses of 2.5, 3.3 or 4.1 gm/kg from the 5th week. Mean maternal peak plasma ethanol concentrations (MPPEC's) ranged from 24 +/- 6 mg/dl at the 0.3 g/kg dose to 549 +/- 71 mg/dl at the 4.1 g/kg dose. Thirty-three live born infants were assessed for abnormalities of physical and behavioral development. Ocular pathology, neuropathologic and neurochemical assessements were done on 31 animals at 6 months postnatal age. Microphthalmia was noted in three of the 26 animals exposed to ethanol. Retinal ganglion cell loss was significantly associated with intra-uterine ethanol exposure. Microphthalmia and retinal ganglion cell loss was observed in both the delayed and full-gestational exposed animals. No structural anomalies were found in the brains via gross inspection or light microscopy. Chemical abnormalities in the striatal nuclei were identified. Striatal dopamine concentrations increased with increasing MPPEC exposure (0-249 mg/dl) among animals exposed weekly to ethanol throughout gestation. Striatal dopamine concentrations decreased with increasing MPPEC exposure (260-540 mg/dl) among animals whose weekly exposure to ethanol was delayed until the 5th week of gestation. The same pattern of association was also noted between MPPEC and ultrastructural alterations in the caudate nucleus. The extent of ultrastructural alterations increased with increasing MPPEC among the full-gestational exposed animals and decreased with increasing MPPEC among the delayed-dose animals.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1989

The major histocompatibility complex, MnLA, of pigtailed macaques: definition of fifteen specificities.

The major histocompatibility complex (MHC) of pigtailed macaques (Macaca nemestrina, Mn) is defined and designated as MnLA. Twenty-nine alloantisera were generated by fullsib alloimmunization and tested against a panel of 220 unrelated animals. The reactivities of different alloantisera were analyzed statistically in pairwise comparisons. Using 2 X 2 contingency tables, we calculated chi 2 independence, chi 2 allelism, and correlation coefficient values. Initially, specificities were defined by significant associations of certain sera, but some sera defined specificities individually. In all, 15 specificities were defined, and by family studies and negative correlation coefficients, a two-locus model was evident. Genetic analyses, together with statistical applications, revealed that the behavior of these specificities is consistent with the nature of MHC in other primate species, including man.

Alleles↗
PubMed1989

Ovarian cyclicity, hormones, and behavior as markers of aging in female pigtailed macaques (Macaca nemestrina).

Age-related differences in reproductive function were studied to identify variables suitable for a battery of noninvasive tests used to measure aging rate. Twenty-seven adult female pigtailed macaques, ranging in age from 8 to 31 years, were studied in a cross-sectional design. Perineal tumescence, menses, and activity in the home environment were recorded daily. Sexual behavior, when paired with unfamiliar males of three age groups, was observed six times in the early follicular phase of two ovarian cycles. Estradiol, LH, and FSH were measured twice during the same time period. Of the behavioral measures, mount, present, and activity were found to be lower in old than in young females. Of the physiological measures, ovarian cyclicity was less regular, estradiol was lower, and FSH and LH were higher in old compared to young females. Correlations between measures suggested two dimensions of reproductive function, a behavioral dimension and a physiological dimension.

Aging↗
PubMed1988

Primate research and "psychological well-being".

In Mark Crawford's News & Comment article "Superconductor funds flat" (4 Mar., p. 1089), Robert J. Birgeneau was reported to have had his grant cut to $4.4 million. That National Science Foundation grant actually covers the Massachusetts Institute of Technology's Materials Research Laboratory and supports 40 faculty members. Birgeneau's personal grant was reduced from $125,000 in 1987 to $122,000 for this year.

Animal Welfare↗
PubMed1988

Physical anomalies and developmental delays in nonhuman primate infants exposed to weekly doses of ethanol during gestation.

Ethanol was orally administered once per week to 54 gravid pigtailed macaques (Macaca nemestrina) in doses of 0.0, 0.3, 0.6, 1.2, 1.8, 2.5 or 4.1 gm/kg from the 1st week in gestation or in doses of 2.5, 3.3, or 4.1 gm/kg from the 5th week. Mean maternal mean peak plasma ethanol concentrations (MPPEC) ranged from 24 +/- 6 mg/dl at the 0.3 gm/kg dose to 549 +/- 71 mg/dl at the 4.1 gm/kg dose. Thirty-three viable infants were followed from birth to 6 months of age and assessed for growth, health, congenital anomalies and developmental rate. Facial anomalies, growth deficiency, or central nervous system dysfunction were found in 57% of the alcohol-exposed animals. No animal showed all the features of the human fetal alcohol syndrome. Ten of the twelve animals (83%) with mean MPPEC above 140 mg/dl had evidence of a teratogenic impact. The animals with full gestational exposure to ethanol and mean MPPEC between 140 and 249 mg/dl had much more severe and consistent cognitive abnormalities than the animals with delayed gestational exposures, even though the latter were exposed to mean MPPEC between 260 and 540 mg/dl. Conclusions from this study included: 1) ethanol-related behavioral teratogenesis occurred without accompanying physical anomalies, 2) measurable teratogenic effects from weekly exposures occurred only at intoxicating doses of ethanol, and 3) early gestational exposure to ethanol appeared to be more damaging to cognitive function than later and considerably greater alcohol exposure.

Animals↗
PubMed1988

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonian syndrome in Macaca fascicularis: which midbrain dopaminergic neurons are lost?

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) produces, in both human and non-human primates, a syndrome very similar to idiopathic Parkinson's disease. The syndrome is associated with degeneration of the dopamine-containing neurons in the substantia nigra, many of which project to the neostriatum. The purpose of the present study was to quantify the regional distribution of midbrain dopamine neurons remaining after MPTP administration to the monkey (Macaca fascicularis) and to develop alternative procedures for maintaining the normal nutrition in MPTP-treated animals. Three monkeys were treated with MPTP and three served as controls. Representative sections were examined from rostral to caudal through the midbrain dopamine cell nuclei and the location of every tyrosine hydroxylase-containing cell was entered into a computer. Midbrain dopamine neuronal cell loss ranged from 36-78%, being most extensive in the two monkeys which exhibited the most severe parkinsonian syndrome. The greatest cell loss (46-93%) occurred in the substantia nigra pars compacta, or nucleus A9, and the loss was primarily in the ventral portion of the nucleus. Contrary to most previous reports, however, there was also a loss of cells in the ventral tegmental area (28-57%) and ventral reticular formation (33-87%), corresponding to nuclei A10 and A8, respectively. Since neuroanatomical tracing studies have shown that the dorsal and lateral portions of the striatum (areas showing the greatest dopamine depletion after MPTP) receive input from cells in the ventral A9 and from cells in the A8 and A10 areas, the present data suggest that MPTP preferentially destroys dopamine cells that project to the striatum (i.e. the mesostriatal cells).

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1987

Primate neostriatal neurons containing tyrosine hydroxylase: immunohistochemical evidence.

We have detected, in monkey caudate nucleus and putamen, neuronal cell bodies containing tyrosine hydroxylase-like immunoreactivity, as revealed by peroxidase-antiperoxidase immunohistochemistry. Many of these cells are distributed in an outer rim of 1-2 mm throughout the anterior-posterior extent of the neostriatum near its borders with the corona radiata; others are embedded in the adjacent white matter, especially near the ventral putamen and nucleus accumbens. Light and electron microscopy indicate that they are small (8-12 micron), bipolar cells with large nuclei. Such neostriatal neurons, containing tyrosine hydroxylase-like immunoreactivity, number in the tens of thousands.

Animals↗
PubMed1987

Pregnancy outcomes after weekly oral administration of ethanol during gestation in the pig-tailed macaque (Macaca nemestrina).

Ethanol was orally administered once per week to gravid pig-tailed macaques (Macaca nemestrina) in doses of 0.3, 0.6, 1.2, 1.8, 2.5, 3.3, or 4.1 g/kg. A control group received a sucrose solution, isocaloric and isovolemic to the highest ethanol dose. Pregnancy was followed after 116 possible conceptions in 54 females. Peak plasma ethanol concentrations (PPECs) ranged from 24 +/- 6 mg/dl at the 0.3 g/kg dose to 549 +/- 71 mg/dl at the 4.1 g/kg dose. An increased rate of spontaneous abortion was related to ethanol exposure at and above 1.8 g/kg (mean PPEC = 205 mg/dl). Pregnancy failure in the first 30 days of gestation increased at doses above 2.5 g/kg. The effect on pregnancy outcome of weekly exposure to ethanol in this nonhuman primate is comparable to available data on humans. The methodology of this study represents an effective model for studying ethanol teratogenesis in a nonhuman primate.

Abortion, Spontaneous↗
PubMed1987

Cross-sectional evaluation of potential biological markers of aging in pigtailed macaques: effects of age, sex, and diet.

The objective of our research was to establish a useful battery of innocuous tests suitable for detecting individual differences in biological aging rate in pigtailed macaques. Data were gathered from more than 60 animals of three age groups (8 to 9, 12 to 17, and 18 to 28 years olds) fed two diets differing in lipid, cholesterol, complex carbohydrate, refined sugar, and sodium chloride content. Candidate variables for an aging battery were identified in a cross-sectional analysis by performing a three-way analysis of variance (ANOVA) for the effects of age, sex, and diet on each of 72 variables. Twenty-eight variables were found to be influenced by age. By examining patterns of differences among means, 20 variables were identified that show promise of being useful, including, for example, rectal body temperature, blood albumin, immunoglobulin A, fingernail growth rate, bone thickness, and blood calcium. The set of variables used to estimate biological aging might not be identical for all age-sex classes.

Aging↗
PubMed1986

Pharmacokinetics of ethanol in pigtailed macaques: intersubject variability and effect of subchronic administration.

The pharmacokinetics of IV ethanol (0.6 g/kg) were examined in 11 male colony-bred pigtailed macaques (Macaca nemestrina) aged 3 to 13 years. The animals were either chaired during blood sampling (4 hr) or connected to a tether system that allowed injections and blood sampling while the animal moved freely about its cage. In all instances, ethanol pharmacokinetics could be described by a single Michaelis-Menten function; inclusion of a parallel first-order rate constant to account for non-alcohol dehydrogenase elimination of ethanol did not improve the fit. Volume of distribution was 0.802 +/- 0.054 L/kg (mean +/- SD), Km (the apparent in vivo Michaelis constant) was 0.063 +/- 0.022 micrograms/ml, and Vmax was 0.199 +/- 0.039 g/kg/hr. The pharmacokinetic parameter values of chaired and tethered monkeys did not differ. Three of the tethered monkeys received 3 g/kg of ethanol daily for two weeks by IV infusion (subchronic administration). Ethanol pharmacokinetics, determined on five occasions before and five occasions after subchronic ethanol administration, showed that the treatment did not alter the volume of distribution or Km in any of the three monkeys. The value of Vmax increased approximately 23% in one of the three monkeys that received subchronic ethanol; this increase may have been due to a single, inadvertent administration of a 4.5-g/kg dose over a 20-min period. Vmax did not change in the other two monkeys.

Animals↗