By the 1820s, morphine was a mainstream drug in pharmaceuticals and medicine (and still is today, hence its neurological importance) . When the Civil War rolled around in America in the 1870s, it was injected into injured soldiers to manage their pain but largely exposed a scary neurological side effect of prolonged painkiller use: addiction (2). The artifact above shows a Civil War nurse surrounded by injured and addicted soldiers (3). Many soldiers were sent home due to endless cravings for morphine. Their opioid receptors were evidently fried from repeated exposure to morphine and their bodies were physiologically dependent on the substance.

Sources:

1) https://protomag.com/neurology/morphine-at-200/

2) https://pubmed.ncbi.nlm.nih.gov/17152761/#:~:text=In%20the%20early%201800s%20sciences,adverse%20effects%20and%20abuse%20potential.

3) https://daily.jstor.org/the-post-civil-war-opioid-crisis/

Because of its other side effects that were discovered in the mid-1900s, such as heart and liver failure, chloroform is no longer used as an anesthetic in medical settings anymore (3). However, chloroform's creation was a notable milestone in neuroscience because such a strong anesthetic had never been used in medical settings before while also being reversible. It allowed for much more seamless surgeries when patients were easily put to sleep with a loss of sensation. It also paved the way for other safer, more effective anesthetics to be developed and marketed.

Sources:

1) https://pubs.asahq.org/anesthesiology/article/121/6/1235/13923/The-Chloroform-Still-of-Dr-Samuel-Guthrie-Jr

2) https://assets.publishing.service.gov.uk/media/5a7d6370e5274a02dcdf434f/Chloroform_Toxicological_Overview.pdf

3) https://www.history.com/topics/inventions/ether-and-chloroform

In 1855, once coca reached Europe via trade routes, physician and psychiatrist Friedrich Gaedcke collected some and isolated cocaine in a lab in Germany (1). While Gaedcke first introduced the chemical in its pure form to scientific community in Europe, it was Sigmund Freud who publicized and popularized cocaine's stimulating and euphoric effect on the brain and body.

Freud studied the dose-dependent relationships between cocaine and mood, hand strength, perception, and a number of other functions (1). He found that in the CNS, cocaine blocks neurotransmitter reuptake transporters, most notably the dopamine reuptake transporter (DAT) and the norepinephrine reuptake transporter (NET), allowing feel-good neurotransmitters to remain in the synapse for longer periods of time and illicit a stimulating effect on the nervous system.

The drug slowly crept up in a number of both European and American products in the late 19th century from that point on. It was enjoyed recreationally in drinks such as the wine Vin Mariani, and also in over-the-counter products for headache, neuralgia, melancholy, and toothache as shown in the image above (2). Cocaine's popularization was notable and significant in neuroscience because we now know how addictive the high one achieves from cocaine is and how cycles of addiction can damage the brain.

Sources:

1) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6197930/

2) https://oddathenaeum.com/cocaine-the-early-years/

Above is a photo of his experimental results, Later, in 1827, it was identified by French chemist Pierre-Joseph Pelletier in tea leaves, indicating that caffeine had multiple natural sources.

Some doctors believed coffee to be a fever reducer due its caffeine content (1). While we know this to be untrue today, caffeine is still a very prominent drug in popular culture today. Most of us start our day with some form of drinkable caffeine, whether it be coffee, tea, or energy drinks (2).

The observed physiological effects of caffeine were not actually distinguished until the later 20th century, but we know today that caffeine is a natural stimulant and its effects include enhanced problem solving, quicker information processing, and improved cognitive function. We also know that relative to many other molecules, caffeine is quickly absorbed into the bloodstream and has a short half-life, so its short-term stimulating effect makes it a drug of choice for many people.

Sources:

1) https://blogs.loc.gov/inside_adams/2022/10/caffeine/

2) https://www.hsph.harvard.edu/nutritionsource/caffeine/#:~:text=Caffeine%20is%20naturally%20found%20in,added%20to%20beverages%20and%20supplements.

English and Japanese researchers George Oliver and Jokichi Takamine, respectively, began investigating the adrenal medulla in the mid-19th century.

Oliver displayed the effect of extract from the adrenal medulla on heart rate and blood pressure, and found that the substance, which would soon be named adrenaline, increases both by promoting arteriole contraction (1). Above is a photo of Oliver and the staff at a formal presentation of his findings to the Physiological Society on March 10, 1894 at University College (2).

This discovery was a huge milestone in neuroscience as it highlighted a major intersection between the nervous system and endocrine system - a substance that functions as a hormone, neurotransmitter, and even as a drug for allergic reactions. Adrenergic receptors are hence understandably plentiful in the body, and are found on both target organs from the bloodstream and cells from synapses.

In 1899, John Abel, an American biochemist and pharmacologist at Johns Hopkins University, finally identified adrenaline's active ingredient to be epinephrine (1). Extensive research was done after this point into the 20th century to further hone in on adrenaline's other roles in the body. Today, we know its primary job is stimulating the fight or flight response to stress in the sympathetic nervous system and keeping us alert in dangerous or threatening situations.

Sources:

1) https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(15)00087-9/fulltext#:~:text=In%201894%2C%20at%20the%20University,steel%20hooks%2C%20fine%20cotton%20threads%2C

2) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2466464/pdf/postmedj00373-0007.pdf

The modern e-cigarette was invented by Chinese pharmacist and inventor Hon Lik in 2003. His goal was to create a safer alternative to smoking after the loss of his father. While his first model might have done just that, the number of e-cigarette and vape manufacturers have since skyrocketed, and many add harmful heavy metals and chemicals in addition to the desired stimulant, nicotine. Just a few of these models are shown above (1).

The popularity of the e-cigarette worldwide since the early 2000s can be attributed to a number of factors. For one, they are reusable, convenient, and easily attainable at almost any gas station. More than anything, they allow a strong, fast hit of nicotine. Before these devices, the only marketed inhalable form of nicotine that allowed the drug to reach the brain almost as quickly was the cigarette. Among the younger generation, e-cigarettes seem to be the preferred method of drug administration regardless of unknown health and cognitive risks.

Research on e-cigarettes has uncovered many risks to users, including nicotine addiction, lack of impulse control, and mood disorders. Excessive exposure to nicotine can also change our synapses to harm the regions of our brain associated with learning and attention (2). As e-cigarettes are marketed heavily towards teens and younger adults, this is a real area of concern in neuroscience as the next few generations may be more susceptible to irreversible changes in the brain.

Sources:

1) https://courses.lumenlearning.com/suny-buffalo-environmentalhealth/chapter/e-cigarettes/

2) https://e-cigarettes.surgeongeneral.gov/knowtherisks.html#:~:text=Brain%20Risks,-The%20part%20of&text=These%20risks%20include%20nicotine%20addiction,that%20control%20attention%20and%20learning.

He is credited with the discovery of the reuptake of neurotransmitters, and further published work revealing the starts of processes involved in storage, release, reuptake, and communication of neurotransmitters (2).

Axelrod also studied the metabolism of drugs, and provided insights on how their metabolites can produce new reactions within the CNS and body. He was an expert on the mechanism of antidepressant drugs, and explored how different concentrations of certain drugs in the body led to different neurotransmitter levels and changes in mood (2).

I believe he is the best guide for this exhibit because his contributions to neurology have been pivotal in our understanding of neural communication today, and more specifically, neural communication under the influence of a multitude of different drugs and substances.

Sources:

1) https://en.wikipedia.org/wiki/Julius_Axelrod

2) https://profiles.nlm.nih.gov/spotlight/hh/feature/prize