Squirrel monkey, cannabinoids

Although animal studies indicate transfer of A -THC into the milk, comparable research has not been done on humans. It is difficult to extrapolate from animal studies to humans. The only primates studied, squirrel monkeys, are known to metabolize A9-THC differently than humans. (15) In addition, lactating human mothers in the general population ingest both A9-THC and other cannabinoids (e.g., CBN, CBD) by smoking cannabis. Information is not currently available regarding either transfer of cannabinoids into the milk of lactating humans or the effects of maternal cannabis use on infant development. 

Furthermore, although many earlier attempts to obtain reliable self-administration behavior with THC were unsuccessful (33), some success has been obtained recently. Squirrel monkeys were trained to self-adminis-ter low doses of THC (2 pig/kg per injection), but only after the animals had first been trained to self-administer cocaine (39). THC is difficult to administer intravenously, but these authors succeeded, perhaps in part because they used doses comparable to those to which human cannabis users are exposed, and because the potent synthetic cannabinoids are far more water-soluble than THC, which makes intravenous administration easier. Mice could be trained to self-administer intravenous WIN55212-2, but CBi receptor knockout animals could not (40). 

Nakamura-Palacios EM, Winsauer PJ, Moerschbacher JM (2000) Effects of the cannabinoid hgand SR141716A alone or in combination with A9-tetrahydrocannabinol or scopolamine on learning in squirrel monkeys. Behav Pharmacol 11 377-389... 

Justinova, Z., Solinas, M., Tanda, G., Redhi, G.H. and Goldberg, S.R. (2005) The endogenous cannabinoid anandamide and its synthetic analog R(+)-methanandamide are intravenously self-administered by squirrel monkeys, J Neurosci, 25 5645-5650. 

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