For years it had been suspected that opiates had specific binding sites in the brain. There were several attempts to locate these sites, but the existing technologies were unable to distinguish between the non specific binding to tissue and the specific binding to receptors. It must be mentioned here that the first attempt to actually measure specific opiate binding was in the laboratory of Dr. Vincent Dole (Ingolia & Dole, 1970). Although the technology was not available at that time he laid the foundations for the discovery of opiate receptors.

By the early 1970s scientific technology had evolved to the point where the discovery of opiate binding sites seemed almost inevitable. The first to shake the scientific community was Solomon Snyder and his student, Candice Pert of John Hopkins University (Pert & Snyder, 1973). Using a technique developed by Avram Goldstein of Stanford University, Snyder and Pert located the elusive opiate receptor (Goldstein, Lowney & Pal, 1971). That same year two other groups headed by Eric J. Simon of New York University (1973) and Lars Terenious in Uppsala, Sweden (1973) demonstrated specific opiate binding in nervous tissue. The treasure hunt had begun! "For why," Goldstein asked, "would God have made opiate receptors unless he had also made an endogenous morphine-like substance?"

In the mid-1960s Choh Li of the University of California at Berkeley had isolated a pituitary hormone which he named B-Lipotropin (Li, 1964). He noted that one portion of this hormone had analgesic properties. One year after the discovery of the receptor sites John Hughes at the laboratory of Hans Kosterlitz in Aberdeen, Scotland reported the existence of an endogenous morphine-like substance which they later purified and named Enkephalin for "in the head" (Hughes, 1975a; Hughes, 1975b; Kosterlitz, 1976) The Aberdeen group recognized that the peptide sequence of Enkephalin was contained within Li's B-Lipotropin. Li would later name the other endogenous morphine-like peptides, which also come from his pituitary hormone, Endorphin for "morphine within."

Today the term opioid is used for all endogenous morphine-like substances, including Dynorphin another brain opioid peptide system found by Avram Goldstein (Goldstein, Tachibana, Lowney, Hunkapiller & Hood, 1979). Other psychoactive peptides have been discovered and isolated using the techniques developed in these laboratories. In 1978 Solomon Snyder, John Hughes and Hans Kosterlitz shared the Lasker Award for their discoveries. Paralleling the discovery of Enkephalins, Endorphins and opiate receptors have been advances in the field of neuroscience. These advances have led to many exciting discoveries and generated a new interest in the functioning of the brain. We have entered a new era in our understanding of human behavior.

Most psychoactive drugs come from plants,and there are hundreds of plants with psychoactive properties. People have put most of them to work in some part of the world or another at one time or another. Often drugs taste bad, are weak, or have unwanted side affects.

Morphine, cocaine, and mescaline are all examples of drugs that occur in plants but are commonly available in refined form as white powders, sold both legally and illegally. Some of them, such as mescaline, can easily be synthesized in laboratories, but even when they are, we can still call them natural drugs because the molecules already exist in nature. Others, such as cocaine and morphine, have more complex molecular structures.

Pharmacologists often take refined natural drugs and change their chemical structures to vary their properties. A very simple change is to combine an insoluble drug from a plant with an acid to make a water-soluble salt. In this way the "freebase" form of cocaine, which is usually smoked because it will not dissolve, is turned into cocaine hydrochloride, a water-soluble compound that can be inhaled or injected.

Wholly synthetic drugs are nmade from scratch in the laboratory and do not occur naturallu. Valium, PCP, secobarbitol (Seconal) are examples. It may be that synthetic drugs are the most dangerous of all and the hardest to form good realtionships with, but it is risky to make such sweeping judgements.