Scientists have recently begun to understand how chemicals in marijuana operate on individual cells in the body and other parts in the body despite the long observation that marijuana alters human thinking and behaviour. This knowledge is indeed very vital to determining how marijuana and its component chemicals affect those who use it.
Studies show that cannabinoids create majority of their effects by fastening to proteins called receptors on the surfaces of particular kinds of cells. Various type of this receptor proteins popper the exterior membranes of these cells throughout the entire human body. Each of these receptors distinguishes only very few specific molecules which are collectively known as ligands and when an appropriate ligand attaches to its receptor, it usually sets off a chain of biochemical reactions within the cell. Various drugs including hormones and neurotransmitters put forth their effects by taking the role as ligands at different receptors.
Cannabinoid receptors refer to the cellular receptors that combine THC and its chemical relatives. All vertebrate animals possess such similar kinds of cannabinoid receptors on their cells likewise with some invertebrates including molluscs and leeches. This only indicates that the receptors execute similar functions in a wide variety of animal species. This also emphasizes that cannabinoid receptors have long existed since vertebrates first advanced more than 500 million years ago.
Scientists have presently identified two fundamental kinds of cannabinoid receptors – CB1 and CB2 whereby the CB1 receptors are extremely copious in the brain. The brain has actually ten times as plenty cannabinoid receptors as morphine receptors, which are accountable for the effects of opiates and heroin including the body’s own endorphins. CB2 receptors, on the other hand, are abundant in the immune system but very rare in the brain.
Cells that bear cannabinoid receptors react to ligand-binding in many ways. When THC connects with CB1 receptors in nerve cells, it activates a flow of reactions which basically delays nerve impulses which in turn have the possibility to slow a person’s reaction time which may be enough even to make driving dangerous. The same process, however, might also dull the pain signals that travel down those nerves, hence, relieving the pain. In the same manner, when THC binds CB1 receptors on white blood cells, it could hinder their natural reaction to infection which ultimately is a bad thing if it lessens a person’s struggle to disease but it could be a good thing if it decreases painful inflammation.
In current years that researchers have found quite a number of natural ligands that unite only to CB1 or CB2, they have synthesized a few selective ligands that although only currently used as research instruments, these compounds actually open doors to start creating novel medicines that are based on cannabinoids. Aside from anandamide which is a compound that also binds to cannabinoid receptors, researchers have also discovered other chemicals being produced by the human body that does the same thing and they are continually in quest for more.
Mack, Alison, Joy, Janet. “Front Matter.” Marijuana As Medicine?: The Science Beyond the Controversy. Washington, DC: The National Academies Press, 2000.