Regnier de Graaf (English spelling), original Dutch spelling Reinier de Graaf, or Latinized Reijnerus de Graeff (30 July 164117 August 1673), was a Dutch physician, physiologist and anatomist who made key discoveries in reproductive biology. He specialized in iatrochemistry and iatrogenesis, and was the first to develop a syringe to inject dye into human reproductive organs so that he could understand their structure and function.
Biography
thumb|Anatomical theater in Delft. Drawing by J.v.d.Star 1776 - Delftthumb|Old Church in Delft by [[Hendrick Cornelisz. van Vliet ]]
De Graaf was born in Schoonhoven in a Roman Catholic family, as the son of a carpenter/engineer (equivalent to a modern architect). He studied medicine in Leuven (1658), Utrecht and Leiden (1663). There his co-students were Jan Swammerdam, Niels Stensen, Ole Borch and Frederik Ruysch, cooperating with professor Franciscus Sylvius, Johannes van Horne and Lucas Schacht. All of them were interested in the organs of procreation and influenced by Rene Descartes' iatrophysical approach. He submitted his doctoral thesis on the pancreas, and in 1665 he went (together with his brother) to France where he further experimented on dogs, cooperating with Pierre Bourdelot. He obtained his medical degree from the University of Angers with Jean Chapelain as his translator. De Graaf died on 17 August 1673 and was buried respectfully on 21 August in the nearby Old Church, Delft on a prominent spot, at the choir.
It has been speculated that he may have committed suicide, but it is more likely it was malaria, typhoid fever or dysentery as in other Dutch cities; De Graaf also invented a practical syringe, described in his third treatise.
Graafian follicles
His eponymous legacy are the Graafian follicles. He himself pointed out that he was not the first to describe them, but described their development. From the observation of pregnancy in rabbits, he concluded that the follicle contained the oocyte, although he never observed it. The mature stage of the ovarian follicle is called the Graafian follicle in his honor, 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 who like De Graaf still assumed that the follicle was the oocyte itself, although De Graaf realized the ovum was much smaller. The discovery of the human egg was eventually made by Karl Ernst von Baer in 1827. De Graaf's contemporary Jan Swammerdam 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 of plagiarism.
Female ejaculation
De Graaf described female ejaculation and referred to an erogenous zone in the vagina that he himself linked with the male prostate; this zone was later reported by German gynecologist Ernst Gräfenberg and named after him as the Gräfenberg Spot or G-Spot. Further, De Graaf described the anatomy of the testicles and collected secretions of the gall bladder and the pancreas.
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 fertilization took place in the ovary. He believed that the seminal vesicles stored spermatozoa.