Cannabinoid intake

Fride E, Foox A, Rosenberg E, et al Milk intake and survival in newborn cannabinoid CBl receptor knockout mice evidence for a CB3 receptor. EurJ Pharmacol 461 27-34, 2003... 

Arnone M, Maruani J, Chaperon F. Selective inhibition of sucrose nd ethanol intake by SR141716a, an antagonist of central cannabinoid (CB1) receptors. Psychopharmacology 1998 132 104-106. 

Conversely, food intake and body weight are reduced by the selective cannabinoid CBl antagonist SR 141716. Tolerance developed to the anorectic effect of SR 141716 within 5 days of chronic treatment, but body weight remained low throughout 14 days of treatment. In contrast, chronic THC treatment (15 days) suppresses intake of food and water (Drewnowski and Grinker 1978). This effect is of short duration, with... 

Endogenous cannabinoid system as a CS362 modulator of food intake. Int J Obes Relat Metab Disord 2003 27(3) ... 

However, urine has no great relevance in quantitative analysis because the analyte concentrations vary depending on the dose, means of administration, physiological status (urinary pH, sex, age, weight, etc.), the time lag between intake and analysis, the addition of adulterants. So the analytical data of urine may only indicate the presence of a substance up to a defined cutoff point the monitoring window (time interval in which a substance can be detected by ordinary analytical methods) varies from a few days for cocaine, amphetamine, methoxyamphetamine to 2-3 weeks for cannabinoids. 

In summary, RIA has two applications in the screening of plasma and urine specimens for cannabis use. Direct analysis of a sample gives an indication of the presence of cannabinoids on a semi-quantitative basis. Quantitation may then be expanded further and more specifically following HPLC separation. The identification of THC and its metabolites in established patterns could form the basis for an estimate of both the quantity of THC absorbed and the time of intake. 

Using in situ radioligand binding, another study reported an increased CB1 density in DLPFC, an effect that was not dependent on previous cannabis use (Dean et al., 2001). In addition, an increased CB1 receptor density in the striatum has been reported, which may have been associated with recent cannabis intake (Dean et al., 2001). Postmortem studies of cannabinoid receptor expression, in particular for the CB1 receptor in PCC, ACC and DLPFC support the involvement of the cannabinoid system in the pathophysiology of schizophrenia. 

Cannabis is known to stimulate appetite, and promote food intake ( the munchies ). The identification of cannabinoid (CB1) receptors in the brain allowed the development of selective antagonist compounds such as Ri-monabant, which was found to suppresses food intake in laboratory animals (Colombo et al. 1998). Clinical trials have shown it to be significantly more effective than placebo in assisting overweight patients lose weight (see Chapter 8). 

Heshmati H, Caplain H, Bellisle F, Mosse M,FauveauC, Le Fur G (2001) SR141716, a selective CB 1 receptor cannabinoid receptor antagonist reduces hunger, caloric intake, and body weight in overweight or obese men. Obes Res 9 70S... 

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