Regnier de Graaf
Encyclopedia
Regnier de Graaf, Dutch spelling Reinier de Graaf or latinized Reijnerus de Graeff (30 July 1641 17 August 1673) was a Dutch
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 physician
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...

 and anatomist
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...

 who made key discoveries in reproductive biology
Reproductive biology
Reproductive biology is a study mainly involving the reproductive system and sex organs. It is closely related to reproductive endocrinology and infertility. also is miotosis and miosis...

. His first name is often spelled Reinier or Reynier.

Biography

De Graaf was born in Schoonhoven
Schoonhoven
Schoonhoven is a city and municipality in the western Netherlands, in the province of South Holland. The municipality has a population of 12,195 , and covers an area of 6.96 km²...

 and perhaps a relative to the De Graeff
De Graeff
De Graeff is an old Dutch patrician family. The family have played an important role during the Dutch Golden Age. They were at the centre of Amsterdam public life and oligarchy from 1578 until 1672...

 regent family.. He studied medicine in Utrecht
Utrecht (city)
Utrecht city and municipality is the capital and most populous city of the Dutch province of Utrecht. It is located in the eastern corner of the Randstad conurbation, and is the fourth largest city of the Netherlands with a population of 312,634 on 1 Jan 2011.Utrecht's ancient city centre features...

 and Leiden. There his co-students were Jan Swammerdam
Jan Swammerdam
Jan Swammerdam was a Dutch biologist and microscopist. His work on insects demonstrated that the various phases during the life of an insect—egg, larva, pupa, and adult—are different forms of the same animal. As part of his anatomical research, he carried out experiments on muscle contraction...

, Niels Stensen and Frederik Ruysch
Frederik Ruysch
Frederik Ruysch was a Dutch botanist and anatomist, remembered for his developments in anatomical preservation and the creation of dioramas or scenes incorporating human parts...

, one of their professors was Franciscus Sylvius
Franciscus Sylvius
Franciscus Sylvius , born Franz de le Boë, was a Dutch physician and scientist who was an early champion of Descartes', Van Helmont's and William Harvey's work and theories...

. (All of them were interested in the organs of procreation). He submitted his doctoral thesis on the pancreas
Pancreas
The pancreas is a gland organ in the digestive and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, and somatostatin, as well as a digestive organ, secreting pancreatic juice containing digestive enzymes that assist...

, and went to France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 where he obtained his medical degree
Doctor of Medicine
Doctor of Medicine is a doctoral degree for physicians. The degree is granted by medical schools...

 from the University of Angers
Angers
Angers is the main city in the Maine-et-Loire department in western France about south-west of Paris. Angers is located in the French region known by its pre-revolutionary, provincial name, Anjou, and its inhabitants are called Angevins....

. While in Paris, he also turned to the study of the male genitalia, which led to a publication in 1668. Back in the Netherlands in 1667, De Graaf established himself in Delft
Delft
Delft is a city and municipality in the province of South Holland , the Netherlands. It is located between Rotterdam and The Hague....

. Since he was a Catholic
Catholic
The word catholic comes from the Greek phrase , meaning "on the whole," "according to the whole" or "in general", and is a combination of the Greek words meaning "about" and meaning "whole"...

 in a mainly Protestant country, he was unable to follow a university career. After the early death of a son, De Graaf died in 1673 at age 32 and was buried in the Oude Kerk
Oude Kerk (Delft)
The Oude Kerk , nicknamed Oude Jan , is a Gothic Protestant church in the old city center of Delft, the Netherlands. Its most recognizable feature is a 75-meter-high brick tower that leans about two meters from the vertical....

 in Delft
Delft
Delft is a city and municipality in the province of South Holland , the Netherlands. It is located between Rotterdam and The Hague....

. The reason for his death is unknown. He was, however, affected by his controversy with Swammerdam (v.i.) and the death of his son. Recent speculation that he may have committed suicide is entirely unfounded. A few months before his death De Graaf recommended, as a correspondent of the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

 in London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

, that attention be paid to Antonie van Leeuwenhoek and his work on the improvement of the microscope
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...

.

Legacy

De Graaf's position in the history of reproduction is unique, summarising the work of anatomists before his time, but unable to benefit from the advances about to be made by microscopy, although he reported its use by Antonie van Leeuwenhoek in 1673. His personal contributions include the description of testicular tubules, the efferent ducts
Efferent ducts
The efferent ducts connect the rete testis with the initial section of the epididymis.There are two basic designs for efferent ductule structure:...

, corpora lutea and to describe the function of the Fallopian tubes and hydrosalpinx
Hydrosalpinx
A hydrosalpinx is a distally blocked fallopian tube filled with serous or clear fluid. The blocked tube may become substantially distended giving the tube a characteristic sausage-like or retort-like shape. The condition is often bilateral and the affected tubes may reach several centimeters in...

.De Graaf may have been the first to understand the reproductive function of the Fallopian tube
Fallopian tube
The Fallopian tubes, also known as oviducts, uterine tubes, and salpinges are two very fine tubes lined with ciliated epithelia, leading from the ovaries of female mammals into the uterus, via the utero-tubal junction...

, described the hydrosalpinx
Hydrosalpinx
A hydrosalpinx is a distally blocked fallopian tube filled with serous or clear fluid. The blocked tube may become substantially distended giving the tube a characteristic sausage-like or retort-like shape. The condition is often bilateral and the affected tubes may reach several centimeters in...

, linking its development to female infertility
Infertility
Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...

. De Graaf also invented a practical syringe
Syringe
A syringe is a simple pump consisting of a plunger that fits tightly in a tube. The plunger can be pulled and pushed along inside a cylindrical tube , allowing the syringe to take in and expel a liquid or gas through an orifice at the open end of the tube...

, described in his third treatise.

Graafian follicles

His eponymous legacy are the Graafian (or ovarian) follicles. He himself pointed out that he was not the first to describe them, but described their development. From the observation of pregnancy
Pregnancy
Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...

 in rabbits, he concluded that the follicle contained the oocyte
Oocyte
An oocyte, ovocyte, or rarely ocyte, is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell which undergoes a mitotic...

, although he never observed it. The mature stage of the ovarian follicle is called
Eponym
An eponym is the name of a person or thing, whether real or fictitious, after which a particular place, tribe, era, discovery, or other item is named or thought to be named...

 the Graafian follicle in his honour, although others, including Fallopius, had noticed the follicles previously (but failed to recognize its reproductive significance). The term Graafian follicle followed the introduction of the term ova Graafiana by Albrecht von Haller
Albrecht von Haller
Albrecht von Haller was a Swiss anatomist, physiologist, naturalist and poet.-Early life:He was born of an old Swiss family at Bern. Prevented by long-continued ill-health from taking part in boyish sports, he had the more opportunity for the development of his precocious mind...

 who like De Graaf still assumed that the follicle was the oocyte itself, although De Graaf realised the ovum was much smaller. The discovery of the human egg was eventually made by Karl Ernst von Baer
Karl Ernst von Baer
Karl Ernst Ritter von Baer, Edler von Huthorn also known in Russia as Karl Maksimovich Baer was an Estonian naturalist, biologist, geologist, meteorologist, geographer, a founding father of embryology, explorer of European Russia and Scandinavia, a member of the Russian Academy of Sciences, a...

 in 1827. De Graaf's contemporary Jan Swammerdam
Jan Swammerdam
Jan Swammerdam was a Dutch biologist and microscopist. His work on insects demonstrated that the various phases during the life of an insect—egg, larva, pupa, and adult—are different forms of the same animal. As part of his anatomical research, he carried out experiments on muscle contraction...

 confronted him after his publication of DeMulierum Organis Generatione Inservientibu and accused him of taking credit of discoveries he and Johannes van Horne had made earlier regarding the importance of the ovary and its eggs. De Graaf issued a rebuttal but was affected by the accusation.

Female ejaculation

De Graaf described female ejaculation
Female ejaculation
Female ejaculation refers to the expulsion of noticeable amounts of clear fluid by human females from the paraurethral ducts through and around the urethra during or before an orgasm...

 and referred to an erogenous zone in the vagina that he himself linked with the male prostate
Prostate
The prostate is a compound tubuloalveolar exocrine gland of the male reproductive system in most mammals....

; later this zone was rediscovered by the German gynecologist Ernst Gräfenberg
Ernst Gräfenberg
Ernst Gräfenberg was a German-born physician and scientist...

 as the G-spot
G-spot
The Gräfenberg Spot, often called the G-Spot, is a bean-shaped area of the vagina. Many women report that it is an erogenous zone which, when stimulated, can lead to strong sexual arousal, powerful orgasms and female ejaculation...

. Further, he described the anatomy of the testicle
Testicle
The testicle is the male gonad in animals. Like the ovaries to which they are homologous, testes are components of both the reproductive system and the endocrine system...

s and collected secretions of the gall bladder and the pancreas
Pancreas
The pancreas is a gland organ in the digestive and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, and somatostatin, as well as a digestive organ, secreting pancreatic juice containing digestive enzymes that assist...

.

Weaknesses

Despite his contributions, De Graaf made a number of errors in addition to believing that the ovum was the follicle. He never actually consulted the ancient texts but merely repeated the accounts of others compounding their inaccuracies. Because he observed rabbits rather than humans, he assumed fertilisation took place in the ovary. He believed that the seminal vesicles stored spermatozoa.

Gallery


Publications


Other sources

  • Houtzager HL. Reinier de Graaf 1641-1673 (Dutch
    Dutch language
    Dutch is a West Germanic language and the native language of the majority of the population of the Netherlands, Belgium, and Suriname, the three member states of the Dutch Language Union. Most speakers live in the European Union, where it is a first language for about 23 million and a second...

    ). Rotterdam: Erasmus publishing, 1991. ISBN 90-5235-021-3.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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