# What Paulescu discovered before the Toronto team *Bucharest – Toronto – Stockholm, 1921–1923* On 31 August 1921, Nicolae Paulescu published proof that pancreatic extract lowers glycemia and ketone bodies in depancreatized dogs. Effective, repeatable clinical treatment in humans came from Toronto in January 1922, after Collip's purification. Historians disagree on what «the discovery of insulin» means. Below: 15 selected moments from the file, and Paulescu's political record, documented. By Marius Comper · 19 September 2026 · 12 min read ## The timeline: 15 selected moments from the file Between 21 April 1921 and 6 November 1923: what happened at 15 selected moments, in Cluj, Iasi, Bucharest, Paris, Liège, Toronto or Stockholm, and how many days after the previous one. Pick the moment above to walk the file step by step; the full list stays below. ### 21 April 1921 — Cluj: Paulescu presents his results *Cluj.* Before the Cluj Biology Society, Paulescu shows that pancreatic extract lowers blood sugar in diabetic dogs. Iasi and Bucharest follow. ### 17 May 1921 — Toronto: Banting and Best begin *Toronto.* 26 days after Cluj, the young surgeon Banting and the student Best start work in Professor Macleod's laboratory, under his direction. Banting's idea dated from 31 October 1920; by August the two had an effective extract in the dog. ### 19 May 1921 — Iasi: Paulescu's second presentation *Iasi.* 2 days after the Toronto start, Paulescu presents his results in Iasi, before the local Biology Society branch. ### 22 June 1921 — The manuscript leaves for Liège *Bucharest.* 34 days after Iasi, Paulescu sends the full paper to the Archives Internationales de Physiologie: Recherche sur le rôle du pancréas dans l'assimilation nutritive. ### 23 June 1921 — Bucharest: the third presentation *Bucharest.* One day after sending the manuscript, Paulescu presents the same results in Bucharest. All three communications reach Paris. ### 23 July 1921 — Paris: 4 notes, 9 experiments *Paris.* 30 days after Bucharest, the Comptes rendus des Séances de la Société de Biologie publishes, in its 23 July session, the 4 short notes with 9 experiments on depancreatized dogs. ### 31 August 1921 — Liège: the full paper appears in print *Liège.* 106 days after Banting and Best had begun their experiments, the Archives publishes the complete paper: the extract lowers glycemia, glycosuria and ketone bodies in depancreatized dogs. ### 14 November 1921 — Toronto: the first Banting–Best communication *Toronto.* 75 days after the Archives paper, Banting and Best present their results at the Toronto physiology Journal Club. A journal paper is next. ### 30 December 1921 — New Haven: Toronto steps onto the stage *Toronto.* 46 days after the Journal Club, Banting presents the extracts at the American Physiological Society meeting in New Haven. ### 11 January 1922 — First human treated: Leonard Thompson, 14 *Toronto.* 12 days after New Haven, the 14-year-old boy receives his first injection at Toronto General Hospital, under the care of the clinician W. R. Campbell. The extract is impure: sterile abscess, almost no effect. ### 23 January 1922 — Collip's purified extract works *Toronto.* 12 days after the first injection, Collip's purified extract is given in repeated daily injections, and Thompson stabilizes. The boy lives on continuous treatment for 13 more years, until 1935. ### 10 April 1922 — Romanian patent no. 6254: pancreina *Bucharest.* 77 days after the successful injection, the Ministry of Industry and Trade grants Paulescu the patent for pancreina and its manufacturing process. ### 5 February 1923 — Paulescu writes to Banting *Bucharest.* With his 1921 publications enclosed, Paulescu asks Banting to recognize his priority. Banting never replies. ### 25 October 1923 — Stockholm: the Nobel goes to Banting and Macleod *Stockholm.* The 19 professors of the Karolinska Institute vote in secret: the prize for the discovery of insulin is shared by Banting and Macleod. Banting willingly shares the money with Best, Macleod with Collip. ### 6 November 1923 — Protest to the Nobel Committee president *Bucharest.* 12 days after the vote of 25 October, Paulescu sends Stockholm his August 1921 paper and demands justice, invoking the priority of his publications. We found no reply from the Committee in the cited sources. ## The experiment: what pancreina did Paulescu worked on depancreatized, hence diabetic, dogs. He injected aqueous pancreatic extract into the jugular vein and tracked sugar and ketone bodies. The effect lasted about 12 hours, peaking 2 hours after the injection. ### Blood sugar fell Glycemia dropped after each injection, sometimes to the temporary disappearance of hyperglycemia. ### Urine sugar fell Glycosuria fell together with blood sugar in the depancreatized dogs. ### Ketones fell Blood and urine ketone bodies visibly decreased in the depancreatized dogs, together with sugar. ### Fever did not reproduce the effect In a control experiment with induced fever up to 38.9 °C, glycemia did not move the same way. Fever alone does not reproduce the measured change in glycemia. > Injection of pancreatic extract into the jugular vein of the diabetic dog led to the decrease and even the temporary suppression of hyperglycemia and glycosuria. > > — Conclusions of the Archives paper, 31 August 1921 In his 1921 publications Paulescu had shown the effect in dogs. In 1923 he gave a refined version to two patients, with limited effect; he did not produce the effective, repeatable clinical treatment achieved at Toronto. ## The controversy: publication priority The priority case turns on four items: the Toronto paper of February 1922, Paulescu's two letters, and the record of the Stockholm vote. A 1969 letter from Best acknowledges a translation error. Historians disagree on what «the discovery of insulin» means: active pancreatic extracts had also been published by Zülzer, Scott, Murlin and Kramer, or Kleiner, and effective clinical treatment came from Toronto. ### The mistranslation, February 1922 In their first paper, Banting and Best write of Paulescu that «injections into peripheral veins produce no effect». Paulescu had written that the same effects are also observed when the extract is injected into a branch of the portal vein, not only into a peripheral vein. The Toronto wording is a mistranslation; whether it was intended stays uncertain, and no evidence shows it decided the Nobel. ### The letter to Banting, 5 February 1923 Paulescu sends Toronto his 1921 publications and asks for recognition of his priority. He receives no reply. ### The Stockholm protest, 6 November 1923 12 days after the vote of 25 October, Paulescu writes to the Nobel Committee president, encloses the August 1921 paper and denounces the violation of his rights. We found no reply from the Committee in the cited sources. ### The secret ballot, 25 October 1923 The 19 professors of the Karolinska Institute share the prize between Banting and Macleod «for the discovery of insulin». Banting willingly shares the money with Best, Macleod with Collip. > He states that injections into peripheral veins produce no effect and his experiments show that second injections do not produce such marked effect as the first. > > — Banting and Best on Paulescu, Journal of Laboratory and Clinical Medicine, February 1922 > Une diminution ou même une suppression passagère de l'hyperglycémie et de la glycosurie s'observent aussi lorsqu'on injecte l'extrait pancréatique, non plus dans une veine périphérique, mais dans une branche de la veine porte. > > — Paulescu, Archives Internationales de Physiologie, 1921, quoted by Rosenfeld et al., Acta Diabetologica, 2023 > I regret very much that there was an error in our translation of Professor Paulescu's article. > > — Charles Best to Ion Pavel, 15 October 1969: an acknowledgment of a translation error. The letter is Best's, though anecdote credits Banting. ## The shadow: Paulescu's political file The same hand that isolated pancreina also wrote and organized antisemitic hatred. The facts below are documented in a 2023 Acta Diabetologica study and in the Elie Wiesel Institute timeline. We do not quote his violent texts. We record dates, offices and numbers. ### 1913: the book He publishes in Bucharest Fiziologia filozofică, subtitled Spitalul, Coranul, Talmudul, Cahalul, Franc-Masoneria, a Judeophobic pamphlet. ### 1922: the National Christian Union He co-founds the National Christian Union with A. C. Cuza, a far-right party. The cited sources give only the year 1922, no exact day. ### 4 March 1923: LANC He co-founds the League for Christian National Defence with A. C. Cuza, a violently antisemitic party. ### 1926: elections and candidacy LANC takes 4.76% of the vote in the general elections. Paulescu runs unsuccessfully for the Senate in Ilfov county. ### 27 August 2003: the cancelled tribute The Romanian Academy, the European Association for the Study of Diabetes and the International Diabetes Federation had agreed on a series of tribute events in Paris. The academic ceremony at the Hôtel-Dieu hospital, with the «N.C. Paulescu» memorial lecture of 27 August 2003, a plaque and sculptures of Paulescu and Lancereaux, was cancelled after the accusation of the European Centre of the Simon Wiesenthal Foundation. No line of the scientific file washes this file, and no line of this file erases the August 1921 publication of the animal evidence. This page keeps both in the light. ## The man, in brief Nicolae Paulescu was born in Bucharest on 30 October 1869. He studied medicine in Paris, took his doctorate in 1897, then returned home in 1900 as head of the physiology chair at the Bucharest Faculty of Medicine. He taught and ran the laboratory until his death in July 1931. (The exact day differs from source to source, so this page gives only the month.) The pancreina patent dates from 10 April 1922. ## Quiz: true or false Six statements about the Paulescu case. Answer, then open each explanation. 1. **Paulescu published his animal evidence in 1921, before the Toronto team's first paper.** *True. The full paper appeared on 31 August 1921, and the first Banting–Best paper only in February 1922. Publication alone does not settle the «discovery of insulin» debate.* 2. **Banting and Best quoted Paulescu's work correctly.** *False. They credited him with the claim that injections «produce no effect», a mistranslation of «non plus ... mais». Best acknowledged the translation error in writing on 15 October 1969.* 3. **The 1923 Nobel Prize was shared by Banting and Best.** *False. The prize went to Banting and Macleod, by secret ballot on 25 October 1923. Banting shared his money with Best only afterwards, willingly.* 4. **Paulescu never gave his extract to a human.** *False. His 1921 publications had shown the effect in dogs, and in 1923 he gave a refined version to two patients, with limited effect. Effective clinical treatment came from Toronto.* 5. **Paulescu co-founded a far-right party in 1923.** *True. The League for Christian National Defence, founded 4 March 1923, after the National Christian Union of 1922.* 6. **Paulescu received the Nobel Prize later, for pancreina.** *False. He never received it. He died in July 1931, and the cited sources record no reply from the Committee to his protest of 6 November 1923.* ## Sources Every timeline date comes from a publication or a document with an exact day, and day differences are computed from dates, never copied. Where sources contradict each other or stay silent (the day of death, the founding day of the National Christian Union, the pagination of the Archives paper), the page says what is known and notes the disagreement. The Romanian Academy bibliography lists the Archives paper at pages 86–109; other citations give 85–109, and some syntheses give the total 26. The page does not use the page count as a statistic. Paulescu's violent texts are not quoted. The political file records dates, offices and numbers, pointing to the 2023 study and the Elie Wiesel Institute timeline. ### Paulescu's 1921 publications - [Saceleanu et al. (2021). Centenary of Insulin Discovery: Nicolae Paulescu's Original Contributions, Acta Endocrinologica](https://pmc.ncbi.nlm.nih.gov/articles/PMC8919497/) - [Berthold et al. (2022). Organotherapy of diabetes mellitus (1906–1923): Acomatol. Pancreina. Insulin., Acta Diabetologica](https://www.springermedizin.de/on-the-occasion-of-the-centennial-of-insulin-therapy-1922-2022-i/23868990) - [Insulin: evolution of insulin formulations over 100 years (Diabetologia, 2022): the earlier extracts, the two 1923 patients, Collip's final step](https://pmc.ncbi.nlm.nih.gov/articles/PMC9296014/) - [English translation of the Archives conclusions (hosted by the Paulescu Foundation, PDF, an associative source)](http://fundatiapaulescu.ro/img/pdf/LUCRARI%20PAULESCU%20SI%20ALTII.pdf) - [Historique de la découverte de l'insuline (1993). Histoire des Sciences Médicales](http://www.biusante.parisdescartes.fr/sfhm/hsm/HSMx1993x027x001/HSMx1993x027x001x0061.pdf) - [Romanian Academy, Paulescu's Medical Priorities (full bibliography)](https://acad.ro/sectii2002/proceedingsChemistry/doc2018-3/Art11PaulescuMedicalPriorities.pdf) ### Toronto and the Nobel file - [Insulin's centenary: the birth of an idea (2020). The Lancet Diabetes & Endocrinology](https://pubmed.ncbi.nlm.nih.gov/33129375/) - [University of Toronto, biography of Charles Herbert Best](https://collections.library.utoronto.ca/explore/insulin/about/best) - [The history of the Nobel prize for the discovery of insulin (2021). Diabetes Research and Clinical Practice](https://www.diabetesresearchclinicalpractice.com/article/S0168-8227(21)00178-9/fulltext) - [University of Toronto, Insulin 100 (Leonard Thompson, 23 January 1922)](https://insulin100.utoronto.ca/embed/) - [NobelPrize.org, summary of the 1923 medicine prize](https://www.nobelprize.org/prizes/medicine/1923/summary/) - [J. J. R. Macleod, Nobel lecture (1925): the case treated under W. R. Campbell's care, Collip's purification](https://www.nobelprize.org/prizes/medicine/1923/macleod/lecture/) - [Rosenfeld et al. (2023). The Nobel Prize of Physiology or Medicine, 1923: controversies. Acta Diabetologica](https://pmc.ncbi.nlm.nih.gov/articles/PMC10359383/) - [From pancreatic extracts to artificial pancreas (2010). Avances en Diabetología](https://www.elsevier.es/es-revista-avances-diabetologia-326-articulo-from-pancreatic-extracts-artificial-pancreas-S1134323010650132) - [Deman (2021). The discovery of insulin (the misquote, Best's 1969 letter)](https://orbi.uliege.be/bitstream/2268/312588/1/2021%20DEMAN%20discovery%20insulin.pdf) ### The political record - [Covic et al. (2023). Nicolae C. Paulescu: between scientific creativity and political fanatism. Acta Diabetologica](https://pmc.ncbi.nlm.nih.gov/articles/PMC10520201/) - [Elie Wiesel Institute, Storyline chronology: UNC founded in 1922 by Cuza and Paulescu; LANC on 4 March 1923](https://www.inshr-ew.ro/wp-content/uploads/2020/10/Storyline.pdf) ### Biography - [Nicolae Paulescu (1869 – July 1931): biographical landmarks (a tertiary source)](https://en.wikipedia.org/wiki/Nicolae_Paulescu) --- Researched and built by [Marius Comper](https://mariuscomper.uk/en/) · https://mariuscomper.uk/nicolae-paulescu-insulina/en/