History of Anatomy & Physiology. “What a piece of work is a man, how noble in reason, how...

History of Anatomy

& Physiology

“What a piece of work is a man, how noble in

reason, how infinite in faculties, in form and

moving, how express and admirable; in action, how

like an angel; in apprehension, how like a

god! the beauty of the world; the paragon of

animals; ”(Hamlet 2.2.315-319)

William Shakespeare

A&P history

parallels that of medicine

Grecian period• A&P widely accepted as a

science. • Esteemed physical athletic

competition• Expressed the beauty

of the body in their art.

Hippocrates (460-337 BC)• “Father of Medicine”

–Established principles

of medical practice–1st to attribute diseases to

natural causes rather than the displeasure of the gods

–Used application and reason (theory and observation)

• Recognized “4 body humors” (idea persisted for 200 years)

–Sanguine – liver–Choler-(yellow)/bile/gallbladder–Phlegm – lungs–Melancholic (black bile) – spleen

• A healthy person had a balance of the four humors due to a healthy diet and an optimal environment

• Believed disease was due to an imbalance of the humors

• Used “humoral theory” as a diagnostic tool (in conjunction with clinical observation of symptoms)

• The “art” (method) of medical practice is attributed to him

• Did no dissections

• Hippocratic oath–given to graduating medical

students

–legacy he established through thoughtful, rational, ethical, moral and compassionate patient care.

Aristotle – (384-332 BC)• Pupil of Plato• made careful observations and

classifications of many living things

(including humans)• Laid the foundation for

the field of comparative anatomy in an effort to learn more about human systems

• Wrote first known account of embryology (and pangenesis) that described development of chicken heart.

• Helped refute idea of preformation

(sperm and egg contained miniature adults that grow during development)

• Erroneously believed that heart was seat of intelligence

• function of the brain bathed in fluid, was to cool blood pumped from the heart (contrary to Plato who thought brain was seat of feeling and thought).

• First true anatomist

–First to distinguish tendons from nerves

–First to trace arterial blood pathways

Erasistratus (300 B.C.) “father of physiology”

(Alexandrian School in Egypt)• Authored book on causes of

diseases–included observations

of and relationships between the heart vessels, brain, and cranial nerves

• noted the toxic effects of snake venom on various organs

• described changes in the liver resulting from various diseases

• Although many of his writings were scientific, some not; Ex: he believed cranial nerves carried animal spirits and muscles contracted because of distention by spirits.

• Both Erasistatus and Herophilus were greatly criticized for vivisection. Herophilus (known as a butcher of men) dissected as many as 600 living persons, many for public demonstrations.

• Herophilus first to document studies in neuroscience (cerebrum, cerebellum, sensory vs. motor nerves, cerebral ventricles, brain as a “thinking” organ)

• Erasistratus –

–credited with the pneumatic theory describing heart as a pump.

–Organs were served by arteries, veins and nerves

Roman Era• Stifled scientific advancements

–set the stage for the Dark Ages (Middle Ages)

–Interest shifted from theoretical to practical

–Few dissections were done other than autopsies

• Medicine was not preventative by treatment – mostly soldiers wounded in battle.

• Church played a big part in practice of medicine. Ex: If a pregnant woman died, she could not be buried until the fetus was removed and baptized.

• Claudius Galen (130-201 A.D.)

–Best physician since Hippocrates

–Did only 2 or 3 human dissections due to legal limitations

–limited in knowledge by animal dissections

–Very much an experimentalist

–Ex: •proved a pig heart continued to beat even though the nerve innervating it was cut

•pig could no longer squeal if the vocal cord nerve was cut

• Published over 130 medical articles which served as “gospel” medicine for 1500 years.

• Correctly identified that arteries carried blood (not air as previously believed)

• Helped to make connections between anatomical design and physiological function (“structure implies function”); ex. Diaphragm and its relationship to breathing.

• Encouraged ongoing treatment and follow up of patients in order to discern efficacy of treatment

• Erroneously thought liver, heart and brain injected animal spirits into veins to be transported throughout body

• Middle Ages –

–476 A.D. the fall of the Roman Empire

–Lasted 1000 years

–Dissections were completely outlawed, punishable by burning at the stake

–Mysterious deaths were examined by inspection and palpation

–A few autopsies were done during the plague in order to determine the cause of this dreadful disease

• Ibn Sina (known as Avicenna) wrote over 400 Arabic books in medicine, philosophy, and math. – Texts were leading authority until 6th

century– Establishment of universities and

specialized colleges within aided in field of anatomy

– See http://www.mf.uni-lj.si/acta-apa/acta-apa-00-2/moroni-history.html

for info on Alessandro Achillini and the University of Bologna

Renaissance – 14-16 century

• Characterized by a rebirth of science

• Helped by development of moveable type and publication of many more books

• Obtaining cadavers became a problem with the explosion of scientific inquiry

• Medical students regularly practiced grave robbing until an official decree permitted the bodies of executed criminals to be used as specimens

–Andreas Vesalius (1514-1564) “father of modern anatomy”

•Wrote the definitive anatomy book De Humani Corporis Fabrica which wasbeautifully illustrated and accurately described the various body systems and organs

• book boldly challenged many of Galen’s

• was bitterly confronted by so many Galen anatomists (his former teacher Sylvious included) that he destroyed much of his later unpublished work and ceased his dissections

• 17th –18th Century–William Harvey (1578-1657) –

“father of modern physiology”• Wrote On the Movement of the

Heart and Blood in Animals which proved the continuous circulation of blood within vessels

• Had many of the same problems as Vesalius for many of the same reasons

• Anton van Leeuwenhoek (1632-1723)– A lens grinder who not only developed the

microscope but also techniques for tissue examination, describing blood cells,

– spermatozoa, and the – striped appearance of skeletal muscle.

• The microscope helped develop the etiology of diseases and aided in the discovery of the cure

for some of them.

• 19th-20th Century

–Formation of the cell theory and its implications for a clearer understanding of the structure and functioning of the body

–Johannes Muller (1801-1858)•Noted for applying the sciences of physics, chemistry, and psychology to the study of the human body and thus moved A&P into a comparative science

• With the development of new technology, research became more specialized, detailed, and complex,–this forced the development of new

disciplines and specialties

–Ex: histology, cytology, embryology, neurology, gastroenterology, cardiovascular, kinesiology, reproductive physiology, endocrinology

• Henry Gray – b. 1827

–English anatomist and physiologist

–Admitted as a Fellow to the Royal Society at 33 years of age (very young!)

–Published the definitive “Gray’s Anatomy” in 1858

… and the rest, as they say, “is history”