Immune system cannabinoids

The presence of cannabinoid receptors in the immune system has led to consideration of the effects of cannabis on its function. Cannabinoid receptors have been found in spleen cells (Kaminski et al. 1992). Activation of these receptors would inhibit their function in the immune response. Similar suppressant effects occur on lymphocytes (Diaz et al. 1993). THC and anandamide inhibit macrophage-mediated tumor necrosis (Cabral et al. 1995). Despite these effects, their functional significance remains to be determined. These effects are most likely subtle. 

The endogenous cannabinoid 2-arachidonoyl-glycerol is thought to play important roles both in the brain (Chapter 30) and in the immune system (Chapter 31). Leukocyte 12-oxygenase acts on this compound.360 What products would be expected ... 

These smoked substances interact with the brain s own cannabinoid receptors to trigger dopamine release from the mesolimbic reward system. There are two known cannabinoid receptors, CB1 (in the brain, which is coupled via G proteins and modulates adenylate cyclase and ion channels) and CB2 (in the immune system). The CB1 receptors may mediate not only marijuana s reinforcing properties, but also those of alcohol. There is also an endogenous cannabinoid system (the brain s own marijuana) capable of activating these cannabinoid receptors functionally. These ert-docannabinoids are synthesized by neurons and inactivated by reuptake systems and enzymes in both neurons and glia. 

Much research has focused on marijuana s effects on the immune system. Some research has shown that one type of immune system cell called the macrophage (scavenger cell) is particularly sensitive to THC exposure. Macrophages clear the body of viruses, bacteria, and particles that are inhaled or ingested. These studies found the presence of cannabinoid receptors on macrophages, suggesting that THC can disrupt normal immune system functions and may eventually inhibit the body s natural immune response. 

A peripheral cannabinoid receptor (CB2) was later cloned from a human promyelocytic leukaemic line (HL60) [30], This receptor was shown to be only partially homologous with the brain receptor, and is expressed in cells of the immune system, predominantly on B-cells [31]. 

Opioid and Cannabinoid Receptors are on Cells of the Immune System... 

Schatz AR, Lee M, Condie RB, Pulaski JT, Kaminski NE (1997) Cannabinoid receptors CBl and CB2 a characterization of expression and adenylate cyclase modulation within the immune system. Toxicol Appl Pharmacol 142 278-287. 

The investigations conducted to date on the pharmacological effects mediated by cannabinoid receptors show that the non-psychoac-tive effects of Cannabis derivatives are mediated by CB2 peripheral receptor. Furthermore, the CB2 receptor localization proves that said non-psychoactive effects, i.e. the effects on the immune system, the anti-inflammatory, myorelaxant and antinociceptive effects, as well as the effects on pressure systems, are mediated by said receptor. 

The acquired immunodeficiency S5mdrome (AIDS) epidemic has served to increase awareness that the adverse consequences of drug abuse extend beyond the acute and chronic effects produced by these drugs on the brain. The immune system has received considerable attention because both opioid and cannabinoid receptors have been identified in spleen cells. Additionally, specific effects of several drug classes on immune function are now well documented. These studies not only provide important insights into the potential harm that drugs of abuse inflict on a compromised immune system they provide opportunities to elucidate the mechanism of action these drugs. 

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