Marmosets

Medicinal chemistry has frequently drawn inspiration and important new leads from the examination of natural products, and this was proven to be the case once more. In 1992, researchers at Merck and Glaxo announced, almost simultaneously, the independent discovery of the same new class of natural products from two different fungi. As a consequence, the same family of natural products has two names - the zaragozic acids (Merck)4 or the squalestatins (Glaxo).5 A typical member of the family, zaragozic acid A (squa-lestatin SI) (1) was shown to have a tremendous affinity for squalene synthase (K, = 79 pM for rat microsomal squalene synthase) and could even lower serum cholesterol levels in vivo in a population of marmosets.6... 

In one study with common marmosets, the animals were dosed with diazinon (10, 90, or 130 mg/kg i.m.) and measnrements of erythrocyte cholinesterase inhibition... 

Muggleton, N.G., Smith, A.J., and Scott, E.A.M. et al. (2005). A long term study of the effects of diazinon on steep, the electrocorticogram and cognitive behaviour in common marmosets. Journal of Psychopharmacology 19, 455 66. 

Preliminary data indicate that in the reserpinised rat or MPTP marmoset, the enkephalin agonist (SNC80) reduces PD-like symptoms without causing increased activity, i.e. no trend to dyskinesias. Enadoline, a dynorphin-like kappa opioid agonist also has similar effects in the same models. Whether it would be similar in humans remains to be seen. 

Jolkkonen, J, Jenner, P and Marsden, CD (1995) L-Dopa reverses altered gene expression of substance P but not enkephalin in the caudate-putamen of common marmosets treated with MPTP. Brain Res. Mol. Brain Res. 32 297-307. 

In addition, a recent primate study reported that dietary consumption of soy infant formula reduced the neonatal testosterone surge and increased Leydig cell numbers in the testes of male marmosets. However, the longterm effects on the fertility of the animals has not been determined, and the health implications of these findings for humans are unclear (Sharpe et al,... 

SAUNDERS P T, MILLAR M R, WILLIAMS K, MACPHERSON S, HARKISS D ANDERSON R A, ORR B, GROOME N p, scoBiE G, FRASER H M (2000) Differential expression of estrogen receptor alpha and beta and androgen recepto in the ovaries of marmosets and humans. Biol Reprod. 63 1088-95. 

SHARPE R M, MARTIN B, MORRIS K, GREIG I, MCKINNELL, MCNEILLY A S, WALKER M (2002) Infant feeding with soy formula mflk effects on the testis and on blood testosterone levels in marmoset monkeys during the period of neonatal testicular activity. Human Reproduction. 17 1692-1703. 

Homung, J.-P. Fritschy, J.-M. and Fork, I. Distribution of serotonergic axons forming pericellular arrays in the cerebral cortex of the marmoset monkey. Abstract. Experientia 43 686, 1987. 

VN neurogenesis in Common Marmosets (Callithrix jacchus) was detected in the late embryo from about E70 (gestation stage 19) (Phillips, 1976). At birth, these monkeys do show a distinct VNO, but one with... 

The ability to compare semiochemical patterns and to assess degrees of similarity is a likely mechanism underlying the establishment, and eventually the maintenance of genetic divergence. Amongst Tamarins (Saguinus spp.) and Marmosets, both for within- and between- (related) species distinctions, the complexity of their scent marks provides a discriminatory mechanism (Epple et ai, 1987 Smith et al., 1997). Mixed species groups of these monkeys are enabled to co-exist, to... 

Barrett J., Abbott D. and George L. (1993). Sensory cues and the suppression of reproduction in subordinate female marmoset monkeys, Callithrix jacchus. J Reprod Fertil 97, 301-310. 

Converse L., Carlson A.A., Snowdon C.T., Ziegler T. and Snowdon C.T. (1995). Communication of ovulatory state to mates by female Pygmy Marmosets, Cebuella pygmaea. Anim Behav 49, 615-621. 

Evans C.S. and Grigorieva E.V. (1995). Morphology of the vomeronasal organ in two South American primates, Red-Bellied Tamarin (Saguinus labiatus) and Dwarf Marmoset (Cebuella pygmaea) histology and lectin histochemistry. Adv Biosciences 93, 31-42. 

Fuchs E., Rosenbusch J. and Anzenberger G. (1991). Urinary protein pattern reflects social rank in male Common Marmosets. Folia Primatol (Basel) 57, 177-180. 

Phillips I.R. (1976). Embryology of Common Marmoset (Callithrix jacchus). Adv Anat Emb Cell Biol 52, 1-47. 

Rylands A. (1985). Tree-gouging and scent marking by marmosets. Anim Behav 33, 1365-1367. 

Smith T.E. and Abbott D.H. (1998). Behavioral discrimination between circumgenital odor from peri-ovulatory dominant and anovulatory female common marmosets (Callithrix jacchus). Am J Primatol 46, 265-284. 

Smith T.E., Abbott D.H., Tomlinson A. and Mlotkiewicz J. (1997). Differential display of investigative behavior permits discrimination of scent signatures from familiar and unfamiliar socially dominant female marmoset monkeys (Callithrix jacchus). J Chem Ecol 23, 2523-2546. 

Taniguchi K., Matsusaki Y., Ogawa K. and Saito T.R. (1992). Fine structure of the vomeronasal organ in the Common Marmoset, Callithrix jacchus. Folia Primatol (Basel) 59, 169-176. 

Marmoset, adult 241 Am in potato powder single gavage dose, 2.0 ng 0.06 Absorption estimate based on comparisons with liver and carcass 241 Am after an intraperitoneal dose Ham et al. 1994... 

Marmoset, About 3.0 mg/kg BW LD50, single oral dose 14, 15... 

Brown, A.W., R.D. Verschoyle, B W. Street, and W.N. Aldridge. 1984. The neurotoxicity of trimethyltin chloride in hamsters, gerbils and marmosets. Jour. Appl. Toxicol. 4 12-21. 

Subcutaneous injection marmoset monkey, Persistent altered blood chemistry 16, 17... 

Neubert, N., T. Wiesmuller, K. Abraham, R. Krowke, and H. Hagenmaier. 1990. Persistence of various polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs and PCDFs) in hepatic and adipose tissue of marmoset monkeys. Arch. Toxicol. 64 431-442. 

Dimethylarsinic acid is the major metabolite of orally administered arsenic trioxide, and is excreted rapidly in the urine (Yamauchi and Yamamura 1985). The methylation process is true detoxification, since methanearsonates and cacodylates are about 200 times less toxic than sodium arsenite (NAS 1977). The marmoset monkey (Callithrix jacchus), unlike all other animal species studied to date, was not able (for unknown reasons) to metabolize administered As+5 to demethylarsinic acid most was reduced to As+3. Only 20% of the total dose was excreted in urine as unchanged As+5, and another 20% as As+3. The rest was bound to tissues, giving distribution patterns similar to arsenite (Vahter and Marafante 1985). Accordingly, the marmoset, like the rat, may be unsuitable for research with arsenicals. 

Vahter, M. and E. Marafante. 1985. Reduction and binding of arsenate in marmoset monkeys. Arch. Toxicol. 57 119-124. 

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